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3<title>Sensors FAQ for lm_sensors version 2.14</title>
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22<h1 class="settitle">Sensors FAQ for lm_sensors version 2.14</h1>
23Copyright (C) 1998 - 2005<br>
24Frodo Looijaard,<br>
25<a href="mailto:phil..at..netroedge.com">Philip Edelbrock</a>,<br>
26and<br>
27<a href="mailto:mdsxyz123..at..yahoo.com">Mark Studebaker</a><br>
28
29   <div class="shortcontents">
30<h2>Short Contents</h2>
31<ul>
32<li><a href="#toc_Top">lm_sensors</a></li>
33<li><a href="#toc_Overview">1 PC and Sensor Overview</a></li>
34<li><a href="#toc_Basics">2 Sensor and Bus Basics</a></li>
35<li><a href="#toc_Installation">3 Installation and Management</a></li>
36<li><a href="#toc_Problems">4 Problems</a></li>
37<li><a href="#toc_Help">5 How to Ask for Help</a></li>
38<li><a href="#toc_Contribute">6 How to Contribute</a></li>
39<li><a href="#toc_Version-1-Specifics">7 Version 1 Specific Questions</a></li>
40<li><a href="#toc_Document-Revisions">Appendix A Revision History of This Document</a></li>
41</ul>
42</div>
43
44   <div class="contents">
45<h2>Table of Contents</h2>
46<ul>
47<li><a name="toc_Top" href="#Top">lm_sensors</a>
48<li><a name="toc_Overview" href="#Overview">1 PC and Sensor Overview</a>
49<ul>
50<li><a href="#Section-1_002e1">1.1 What sensors are available on my PC?</a>
51<li><a href="#Section-1_002e2">1.2 What can a sensor chip like the "LM78" do?</a>
52<li><a href="#Section-1_002e3">1.3 Where do I find out more about any of these chips?</a>
53</li></ul>
54<li><a name="toc_Basics" href="#Basics">2 Sensor and Bus Basics</a>
55<ul>
56<li><a href="#Section-2_002e1">2.1 How are these sensors read?</a>
57<li><a href="#Section-2_002e2">2.2 What is the SMBus? And the I2C bus?</a>
58<li><a href="#Section-2_002e3">2.3 I don't have an ISA bus!</a>
59<li><a href="#Section-2_002e4">2.4 What sensors do processors have?</a>
60<li><a href="#Section-2_002e5">2.5 How often are the sensor values updated?</a>
61<li><a href="#Section-2_002e6">2.6 How are alarms triggered?</a>
62</li></ul>
63<li><a name="toc_Installation" href="#Installation">3 Installation and Management</a>
64<ul>
65<li><a href="#Section-3_002e1">3.1 Why so many modules, and how do I cope with them?</a>
66<li><a href="#Section-3_002e2">3.2 How do I know which chips I own?</a>
67<ul>
68<li><a href="#Section-3_002e2">3.2.1 What chips are on motherboard XYZ?</a>
69<li><a href="#Section-3_002e2">3.2.2 Do you support motherboard XYZ?</a>
70<li><a href="#Section-3_002e2">3.2.3 Do you support chip XYZ?</a>
71<li><a href="#Section-3_002e2">3.2.4 Anybody working on a driver for chip XYZ?</a>
72</li></ul>
73<li><a href="#Section-3_002e3">3.3 Which modules should I insert?</a>
74<li><a href="#Section-3_002e4">3.4 Do I need the configuration file <span class="file">/etc/sensors.conf</span>?</a>
75<ul>
76<li><a href="#Section-3_002e4">3.4.1 The labels for the voltage and temperature readings in <span class="command">sensors</span> are incorrect!</a>
77<li><a href="#Section-3_002e4">3.4.2 The min and max for the readings in <span class="command">sensors</span> are incorrect!</a>
78<li><a href="#Section-3_002e4">3.4.3 The min and max settings in <span class="file">/etc/sensors.conf</span> didn't take effect!</a>
79<li><a href="#Section-3_002e4">3.4.4 One sensor isn't hooked up on my board!</a>
80<li><a href="#Section-3_002e4">3.4.5 I need help with <span class="file">sensors.conf</span>!</a>
81<li><a href="#Section-3_002e4">3.4.6 Do you have a database of <span class="file">sensors.conf</span> entries for specific boards?</a>
82</li></ul>
83<li><a href="#Section-3_002e5">3.5 What about the <span class="samp">No such file or directory</span> warnings when I compile?</a>
84<li><a href="#Section-3_002e6">3.6 I get all kinds of weird compilation errors?</a>
85<ul>
86<li><a href="#Section-3_002e6">3.6.1 <span class="samp">No rule to make target xxxx needed by xxxx</span> - how to fix?</a>
87</li></ul>
88<li><a href="#Section-3_002e7">3.7 It still does not compile or patch!</a>
89<li><a href="#Section-3_002e8">3.8 <span class="command">make install</span> fails on Mandrake kernels</a>
90<li><a href="#Section-3_002e9">3.9 I get unresolved symbols when I <span class="command">modprobe</span> modules (Red Hat especially)</a>
91<li><a href="#Section-3_002e10">3.10 I2C_DRIVERID_ADM1024 undefined (Red Hat especially)</a>
92</li></ul>
93<li><a name="toc_Problems" href="#Problems">4 Problems</a>
94<ul>
95<li><a href="#Section-4_002e1">4.1 My fans report exactly half/double their values compared to the BIOS?</a>
96<ul>
97<li><a href="#Section-4_002e1">4.1.1 Fans sometimes/always read 0!!</a>
98<li><a href="#Section-4_002e1">4.1.2 I doubled the fan divisor and the fan still reads 7000!</a>
99</li></ul>
100<li><a href="#Section-4_002e2">4.2 Why do my two LM75's report "-48 degrees"?</a>
101<li><a href="#Section-4_002e3">4.3 Why do I have two Vcore readings, I have only one processor!</a>
102<li><a href="#Section-4_002e4">4.4 How do those ALARMS work? The current value is within range but there is still an ALARM warning!</a>
103<li><a href="#Section-4_002e5">4.5 My voltage readings seem to drift a bit. Is something wrong?</a>
104<li><a href="#Section-4_002e6">4.6 Some measurements are way out of range. What happened?</a>
105<ul>
106<li><a href="#Section-4_002e6">4.6.1 -5V and -12V readings are way out of range!</a>
107</li></ul>
108<li><a href="#Section-4_002e7">4.7 What are VID lines? Why is the VID reading wrong?</a>
109<li><a href="#Section-4_002e8">4.8 I read sensor values several times a second, but they are only updated only each second or so. Why?</a>
110<li><a href="#Section-4_002e9">4.9 It sometimes seems to take almost a second before I see the sensor reading results. Why?</a>
111<li><a href="#Section-4_002e10">4.10 Can I be alerted when an ALARM occurs?</a>
112<li><a href="#Section-4_002e11">4.11 SMBus transactions on my PIIX4 simply don't work (timeouts happen).  Why?</a>
113<li><a href="#Section-4_002e12">4.12 My BIOS reports a much higher CPU temperature than your modules!</a>
114<li><a href="#Section-4_002e13">4.13 I try to read the raw <span class="file">/proc</span> files, but the values are strange?!?</a>
115<li><a href="#Section-4_002e14">4.14 How do I set new limits?</a>
116<ul>
117<li><a href="#Section-4_002e14">4.14.1 I set new limits and it didn't work?</a>
118</li></ul>
119<li><a href="#Section-4_002e15">4.15 Some sensors are doubly detected?</a>
120<li><a href="#Section-4_002e16">4.16 I ran sensors-detect, but now I get very strange readings?!?</a>
121<li><a href="#Section-4_002e17">4.17 Bad readings from particular chips</a>
122<ul>
123<li><a href="#Section-4_002e17">4.17.1 Bad readings from the AS99127F!</a>
124<li><a href="#Section-4_002e17">4.17.2 Bad readings from the VIA 686A!</a>
125<li><a href="#Section-4_002e17">4.17.3 Bad readings from the MTP008!</a>
126<li><a href="#Section-4_002e17">4.17.4 Bad temperature readings from the SIS5595!</a>
127<li><a href="#Section-4_002e17">4.17.5 Bad readings from a w8378[12]d!</a>
128<li><a href="#Section-4_002e17">4.17.6 Bus hangs on Ali 1543 on Asus P5A boards!</a>
129<li><a href="#Section-4_002e17">4.17.7 Bad readings from LM75!</a>
130<li><a href="#Section-4_002e17">4.17.8 Bad readings from LM78!</a>
131<li><a href="#Section-4_002e17">4.17.9 Bad readings from LM80!</a>
132<li><a href="#Section-4_002e17">4.17.10 Bad readings from it87!</a>
133</li></ul>
134<li><a href="#Section-4_002e18">4.18 How do I configure two chips (LM87) differently?</a>
135<li><a href="#Section-4_002e19">4.19 Dmesg says <span class="samp">Upgrade BIOS</span>! I don't want to!</a>
136<ul>
137<li><a href="#Section-4_002e19">4.19.1 Dmesg says <span class="samp">use force_addr=0xaddr</span>! What address do I use?</a>
138</li></ul>
139<li><a href="#Section-4_002e20">4.20 Sensors says <span class="samp">Can't access procfs/sysfs file</span></a>
140<li><a href="#Section-4_002e21">4.21 Sensors says <span class="samp">No sensors found!</span></a>
141<li><a href="#Section-4_002e22">4.22 Sensors output is not correct!</a>
142<li><a href="#Section-4_002e23">4.23 What is at I2C address XXX?</a>
143<ul>
144<li><a href="#Section-4_002e23">4.23.1 What is at I2C address 0x69?</a>
145<li><a href="#Section-4_002e23">4.23.2 What is at I2C addresses 0x50 - 0x57?</a>
146<li><a href="#Section-4_002e23">4.23.3 What is at I2C addresses 0x30 - 0x37?</a>
147</li></ul>
148<li><a href="#Section-4_002e24">4.24 Sensors-detect doesn't work at all</a>
149<ul>
150<li><a href="#Section-4_002e24">4.24.1 Sensors-detect says "Couldn't open /proc/bus/i2c?!?"</a>
151<li><a href="#Section-4_002e24">4.24.2 Sensors-detect says "Can't open /dev/i2c[-/]0"</a>
152<li><a href="#Section-4_002e24">4.24.3 Sensors-detect doesn't find any sensors!</a>
153</li></ul>
154<li><a href="#Section-4_002e25">4.25 Sensors says <span class="samp">Error: Line xxx: zzzzzzz</span></a>
155<li><a href="#Section-4_002e26">4.26 Sensors only gives the name, adapter, and algorithm for my chip</a>
156<li><a href="#Section-4_002e27">4.27 Sensors says <span class="samp">ERROR: Can't get xxxxx data!</span></a>
157<li><a href="#Section-4_002e28">4.28 Sensors doesn't find any sensors, just eeproms.</a>
158<li><a href="#Section-4_002e29">4.29 Inserting modules hangs my board</a>
159<li><a href="#Section-4_002e30">4.30 Inserting modules slows down my board</a>
160<li><a href="#Section-4_002e31">4.31 Problems on particular motherboards</a>
161<ul>
162<li><a href="#Section-4_002e31">4.31.1 Asus P4B</a>
163<li><a href="#Section-4_002e31">4.31.2 Tyan 2460, 2462</a>
164<li><a href="#Section-4_002e31">4.31.3 Tyan 2466</a>
165<li><a href="#Section-4_002e31">4.31.4 Tyan 2688</a>
166</li></ul>
167<li><a href="#Section-4_002e32">4.32 Problems on particular systems</a>
168<li><a href="#Section-4_002e33">4.33 Problems on 2.6 kernels</a>
169<ul>
170<li><a href="#Section-4_002e33">4.33.1 i2c-viapro and via686a</a>
171</li></ul>
172</li></ul>
173<li><a name="toc_Help" href="#Help">5 How to Ask for Help</a>
174<ul>
175<li><a href="#Section-5_002e1">5.1 What to send us when asking for help</a>
176<li><a href="#Section-5_002e2">5.2 What to do if a module won't insert?</a>
177<li><a href="#Section-5_002e3">5.3 What to do if it inserts, but nothing happens?</a>
178<li><a href="#Section-5_002e4">5.4 What to do if I read only bogus information?</a>
179<li><a href="#Section-5_002e5">5.5 What to do if you have other problems?</a>
180<li><a href="#Section-5_002e6">5.6 What if it just works like a charm?</a>
181<li><a href="#Section-5_002e7">5.7 How do I update a ticket?</a>
182<li><a href="#Section-5_002e8">5.8 How do I follow up on a ticket?</a>
183</li></ul>
184<li><a name="toc_Contribute" href="#Contribute">6 How to Contribute</a>
185<ul>
186<li><a href="#Section-6_002e1">6.1 How to write a driver</a>
187<li><a href="#Section-6_002e2">6.2 How to get CVS access</a>
188<li><a href="#Section-6_002e3">6.3 How to donate hardware to the project</a>
189<li><a href="#Section-6_002e4">6.4 How to join the project mailing list</a>
190<li><a href="#Section-6_002e5">6.5 How to access mailing list archives</a>
191<li><a href="#Section-6_002e6">6.6 How to submit a patch</a>
192<li><a href="#Section-6_002e7">6.7 How to REALLY help</a>
193<li><a href="#Section-6_002e8">6.8 How to get release announcements</a>
194<li><a href="#Section-6_002e9">6.9 How to block spam on the project mailing list</a>
195</li></ul>
196<li><a name="toc_Version-1-Specifics" href="#Version-1-Specifics">7 Version 1 Specific Questions</a>
197<ul>
198<li><a href="#Section-7_002e1">7.1 My manufacturer swears that my mainboard has an SMBus, but your code reports that it can't find it.  What's wrong?</a>
199<li><a href="#Section-7_002e2">7.2 The modules won't load, saying 'SMBus not detected'.</a>
200<li><a href="#Section-7_002e3">7.3 I try to read <span class="file">/proc/sensors</span>, and I get a "No sensor data yet (try again in a few moments)" message. Why?</a>
201<li><a href="#Section-7_002e4">7.4 On my Dell, a LM80 is detected, but all readings are 0!</a>
202</li></ul>
203<li><a name="toc_Document-Revisions" href="#Document-Revisions">Appendix A Revision History of This Document</a>
204</li></ul>
205</div>
206
207<div class="node">
208<p><hr>
209<a name="Top"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Overview">Overview</a>,
210Up:&nbsp;<a rel="up" accesskey="u" href="#dir">(dir)</a>
211<br>
212</div>
213
214<h2 class="unnumbered">lm_sensors</h2>
215
216<p>The lm_sensors package includes a collection of modules for general SMBus
217access and hardware monitoring.  NOTE: this requires special support which
218is not in standard 2.2-vintage kernels.
219
220<ul class="menu">
221<li><a accesskey="1" href="#Overview">Overview</a>:                 PC and Sensor Overview
222<li><a accesskey="2" href="#Basics">Basics</a>:                   Sensor and Bus Basics
223<li><a accesskey="3" href="#Installation">Installation</a>:             Installation and Management
224<li><a accesskey="4" href="#Problems">Problems</a>:                 Problems
225<li><a accesskey="5" href="#Help">Help</a>:                     How to Ask for Help
226<li><a accesskey="6" href="#Contribute">Contribute</a>:               How to Contribute
227<li><a accesskey="7" href="#Version-1-Specifics">Version 1 Specifics</a>:      Version 1 Specific Questions
228<li><a accesskey="8" href="#Document-Revisions">Document Revisions</a>:       Revision History of This Document
229</ul>
230
231<div class="node">
232<p><hr>
233<a name="Overview"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Basics">Basics</a>,
234Previous:&nbsp;<a rel="previous" accesskey="p" href="#Top">Top</a>,
235Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
236<br>
237</div>
238
239<h2 class="chapter">1 PC and Sensor Overview</h2>
240
241<ul class="menu">
242<li><a accesskey="1" href="#Section-1_002e1">Section 1.1</a>:              What sensors are available on my PC?
243<li><a accesskey="2" href="#Section-1_002e2">Section 1.2</a>:              What can a sensor chip like the "LM78" do?
244<li><a accesskey="3" href="#Section-1_002e3">Section 1.3</a>:              Where do I find out more about any of these chips?
245</ul>
246
247<div class="node">
248<p><hr>
249<a name="Section-1_002e1"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-1_002e2">Section 1.2</a>,
250Up:&nbsp;<a rel="up" accesskey="u" href="#Overview">Overview</a>
251<br>
252</div>
253
254<h3 class="section">1.1 What sensors are available on my PC?</h3>
255
256<p>Most PC's built since late 1997 now come with a
257hardware health monitoring chip. This chip may be accessed via the
258ISA bus or the SMBus, depending on the motherboard.
259
260   <p>Some motherboard chipsets, notably the Via 686 and the SiS 5595,
261contain hardware monitor functions.
262
263   <p>This FAQ frequently refers to the "LM78". This chip has been
264obsoleted by National Semiconductor. Most motherboards today contain
265a chip with similar functions.
266
267<div class="node">
268<p><hr>
269<a name="Section-1_002e2"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-1_002e3">Section 1.3</a>,
270Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-1_002e1">Section 1.1</a>,
271Up:&nbsp;<a rel="up" accesskey="u" href="#Overview">Overview</a>
272<br>
273</div>
274
275<h3 class="section">1.2 What can a sensor chip like the "LM78" do?</h3>
276
277<p>The LM78 is a chip made by National Semiconductor which can monitor 7
278voltages (5 positive, 2 negative) from 0 to 4.08V.  The inputs are usually in
279series with voltage dividers which lower the +/- 12V and +/- 5V supplies to
280measurable range.  Therefore, the readings for such inputs need to be
281re-scaled appropriately by software.
282
283   <p>The LM78 also has 3 fan speed monitoring inputs, an internal
284temperature sensor, a chassis intrusion sensor, and a couple maskable interrupt
285inputs.  The LM78 can also relay the processor's (P6 or Pent II) VID lines
286which are hardwired and used to indicate to the power regulator (usually on
287the mainboard close to the processor socket/slot) what voltage to supply to
288the processor.
289
290   <p>The LM78 can be interfaced to a system via the ISA bus and/or the
291SMBus.
292
293   <p>Most other sensor chips have comparable functionality. Each supported
294chip is documented in the <span class="file">doc/chips</span> directory.
295
296<div class="node">
297<p><hr>
298<a name="Section-1_002e3"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-1_002e2">Section 1.2</a>,
299Up:&nbsp;<a rel="up" accesskey="u" href="#Overview">Overview</a>
300<br>
301</div>
302
303<h3 class="section">1.3 Where do I find out more about any of these chips?</h3>
304
305<p>Most semiconductor companies have comprehensive documentation,
306including complete datasheets, on their websites. Analog Devices,
307Dallas Semiconductor, Maxim, and National Semiconductor have the widest selection
308of sensor chips. Their websites are:
309
310     <ul>
311  <li><a href="http://www.analog.com">http://www.analog.com</a>
312  <li><a href="http://www.dalsemi.com">http://www.dalsemi.com</a>
313  <li><a href="http://www.maxim-ic.com">http://www.maxim-ic.com</a>
314  <li><a href="http://www.national.com">http://www.national.com</a>
315</ul>
316
317   <p>Please see the file <a href="http://www2.lm-sensors.nu/~lm78/useful_addresses.html">http://www2.lm-sensors.nu/~lm78/useful_addresses.html</a>
318for links to other companies' websites.
319
320<div class="node">
321<p><hr>
322<a name="Basics"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Installation">Installation</a>,
323Previous:&nbsp;<a rel="previous" accesskey="p" href="#Overview">Overview</a>,
324Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
325<br>
326</div>
327
328<h2 class="chapter">2 Sensor and Bus Basics</h2>
329
330<ul class="menu">
331<li><a accesskey="1" href="#Section-2_002e1">Section 2.1</a>:              What sensors are available on my PC?
332<li><a accesskey="2" href="#Section-2_002e2">Section 2.2</a>:              What can a sensor chip like the "LM78" do?
333<li><a accesskey="3" href="#Section-2_002e3">Section 2.3</a>:              Where do I find out more about any of these chips?
334<li><a accesskey="4" href="#Section-2_002e4">Section 2.4</a>:              What sensors are available on my PC?
335<li><a accesskey="5" href="#Section-2_002e5">Section 2.5</a>:              What can a sensor chip like the "LM78" do?
336<li><a accesskey="6" href="#Section-2_002e6">Section 2.6</a>:              Where do I find out more about any of these chips?
337</ul>
338
339<div class="node">
340<p><hr>
341<a name="Section-2_002e1"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-2_002e2">Section 2.2</a>,
342Up:&nbsp;<a rel="up" accesskey="u" href="#Basics">Basics</a>
343<br>
344</div>
345
346<h3 class="section">2.1 How are these sensors read?</h3>
347
348<p>Sensor chips reside on either the ISA bus, the SMBus, or both.
349See the file <span class="file">doc/chips/SUMMARY</span> in our package for a list.
350
351   <p>To communicate with chips on the ISA bus, the software uses
352simple I/O reads and writes.
353
354   <p>To communicate with chips on the SMBus, the software must
355use an SMBus interface device, explained below.
356
357<div class="node">
358<p><hr>
359<a name="Section-2_002e2"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-2_002e3">Section 2.3</a>,
360Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-2_002e1">Section 2.1</a>,
361Up:&nbsp;<a rel="up" accesskey="u" href="#Basics">Basics</a>
362<br>
363</div>
364
365<h3 class="section">2.2 What is the SMBus? And the I2C bus?</h3>
366
367<p>The SMBus is the "System Management Bus".  More specifically, it is a
3682-wire, low-speed serial communication bus used for basic health monitoring
369and hardware management. It is a specific implementation of the more
370general I2C (pronunciation: I-squared-C) bus. In fact, both I2C devices
371and SMBus devices may be connected to the same (I2C) bus.
372
373   <p>The SMBus (or I2C bus) starts at the host controller, used for
374starting transactions on the SMBus.  From the host interface, the
375devices communicated with are the <dfn>slave</dfn> devices.  Each slave device has a
376unique 7-bit address which the host uses to refer to that device.
377
378   <p>For each supported SMBus host, there is a separate kernel module
379which implements the communication protocol with the host. Some SMBus hosts
380really operate on the SMBus level; these hosts can not cope with pure I2C
381devices. Other hosts are in fact I2C hosts: in this case, we implement
382the SMBus protocol in terms of I2C operations. But these hosts can also
383talk to pure I2C devices.
384
385<div class="node">
386<p><hr>
387<a name="Section-2_002e3"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-2_002e4">Section 2.4</a>,
388Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-2_002e2">Section 2.2</a>,
389Up:&nbsp;<a rel="up" accesskey="u" href="#Basics">Basics</a>
390<br>
391</div>
392
393<h3 class="section">2.3 I don't have an ISA bus!</h3>
394
395<p>We promise, you do, even if you don't have any old ISA slots.
396The "ISA Bus" exists in your computer even if you don't have ISA slots;
397it is simply a memory-mapped area, 64KB in size (0x0000 - 0xFFFF)
398where many "legacy" functions, such as keyboard and interrupt controllers,
399are found. It isn't necessarily a separate physical bus.
400See the file <span class="file">/proc/ioports</span> for a list of devices living on
401the "ISA Bus" in your system. If you don't like the term "ISA Bus"
402think "I/O Space".
403
404<div class="node">
405<p><hr>
406<a name="Section-2_002e4"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-2_002e5">Section 2.5</a>,
407Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-2_002e3">Section 2.3</a>,
408Up:&nbsp;<a rel="up" accesskey="u" href="#Basics">Basics</a>
409<br>
410</div>
411
412<h3 class="section">2.4 What sensors do processors have?</h3>
413
414<p>Most new processors contain a thermal diode on the die itself.
415The electical properties of all diodes and transistors vary
416slightly with temperature. The thermal diode is exceptionally accurate
417because it is directly on the die. Newer temperature sensor chips,
418like the Analog Devices ADM1021 and clones, and the Winbond chips,
419have circuitry for measuring the the electrical properties of
420an external diode and converting this data to a temperature.
421Any sensor chip listed in <span class="file">doc/chips/SUMMARY</span> in our package which
422has support for more than one temperature supports external temperature sensing.
423
424   <p>Older motherboards and processors without this feature generally use
425an LM75 placed close to the processor. This is much less accurate.
426
427   <p>The Pentium 2 'boxed' processor usually has an LM75 very close to the
428base of the box. It can be read through the SMBus to report the approximate
429temperature of the processor.  The processor also contains an internal
430temperature sensor (of low accuracy) used as a fail-safe to disable the
431processor in case it gets much too hot (usually around 130 degrees C).  And,
432the Pentium 2 also has a hard-wired signal (VID lines) on it's SEC (single
433edge connector) which indicates what power supply is required to operate the
434processor.
435
436   <p>The P6 (Pentium-Pro) may have an LM75 in or just under the socket.
437P6's also have VID lines.
438
439   <p>Pentiums and Pentium w/ MMX do not have VID lines, and sometimes have
440LM75's under the sockets (depends on the mainboard, and how 'modern' the
441mainboard is).
442
443   <p>The P2 Xeon was the first Intel processor to include the SMBus
444interface on the P2 Xeon SEC.
445
446<div class="node">
447<p><hr>
448<a name="Section-2_002e5"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-2_002e6">Section 2.6</a>,
449Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-2_002e4">Section 2.4</a>,
450Up:&nbsp;<a rel="up" accesskey="u" href="#Basics">Basics</a>
451<br>
452</div>
453
454<h3 class="section">2.5 How often are the sensor values updated?</h3>
455
456<p>The LM78, and most other sensor chips like it, reads its sensors one
457by one. A complete scanning sweep will take about 1.5 seconds. The LM78 stops
458readings sensors if you try to access it, so if you access it very often
459(by reading sensor values; writing new limits is safe) it will not find the
460time to update its sensor values at all! Fortunately, the kernel module takes
461care not to do this, and only reads new values each 1.5 seconds. If you
462read the values again, you will get the 'old' values again.
463
464<div class="node">
465<p><hr>
466<a name="Section-2_002e6"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-2_002e5">Section 2.5</a>,
467Up:&nbsp;<a rel="up" accesskey="u" href="#Basics">Basics</a>
468<br>
469</div>
470
471<h3 class="section">2.6 How are alarms triggered?</h3>
472
473<p>It is possible to monitor each sensor and have an alarm go off if
474it crosses some pre-determined limits.  There are two sorts of interrupts
475which can be generated by sensor chips if this happens (it depends a bit on
476the actual chip if both are supported; the LM80, for example, has only
477IRQ interrupts): IRQ interrupts and SMI interrupts.  IRQ stands for
478Interrupt Request and are the interrupt lines you can find in <span class="file">/proc/interrupts</span>.
479SMI stands for System Management Interrupt, and is a special interrupt which
480puts the processor in a secure environment independent of any other things
481running.  SMI is currently not supported by the Linux kernel.  IRQs are
482supported, of course.
483
484   <p>Even if no interrupt is generated, some bits in a status register
485will be set until the register is read the next time. If the alarm condition
486persists after that, the bits will be set on the next scanning sweep, etc.
487
488   <p>Most drivers in our package do not support interrupts at this time.
489
490<div class="node">
491<p><hr>
492<a name="Installation"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Problems">Problems</a>,
493Previous:&nbsp;<a rel="previous" accesskey="p" href="#Basics">Basics</a>,
494Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
495<br>
496</div>
497
498<h2 class="chapter">3 Installation and Management</h2>
499
500<ul class="menu">
501<li><a accesskey="1" href="#Section-3_002e1">Section 3.1</a>:      Why so many modules, and how do I cope with them?
502<li><a accesskey="2" href="#Section-3_002e2">Section 3.2</a>:      How do I know which chips I own?
503<li><a accesskey="3" href="#Section-3_002e3">Section 3.3</a>:      Which modules should I insert?
504<li><a accesskey="4" href="#Section-3_002e4">Section 3.4</a>:      Do I need the configuration file <span class="file">/etc/sensors.conf</span>?
505<li><a accesskey="5" href="#Section-3_002e5">Section 3.5</a>:      What about the <span class="samp">No such file or directory</span> warnings
506<li><a accesskey="6" href="#Section-3_002e6">Section 3.6</a>:      I get all kinds of weird compilation errors?
507<li><a accesskey="7" href="#Section-3_002e7">Section 3.7</a>:      It still does not compile or patch!
508<li><a accesskey="8" href="#Section-3_002e8">Section 3.8</a>:      <span class="command">make install</span> fails on Mandrake kernels
509<li><a accesskey="9" href="#Section-3_002e9">Section 3.9</a>:      I get unresolved symbols when I <span class="command">modprobe</span> modules
510<li><a href="#Section-3_002e10">Section 3.10</a>:     I2C_DRIVERID_ADM1024 undefined (Red Hat especially)
511</ul>
512
513<div class="node">
514<p><hr>
515<a name="Section-3_002e1"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e2">Section 3.2</a>,
516Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
517<br>
518</div>
519
520<h3 class="section">3.1 Why so many modules, and how do I cope with them?</h3>
521
522<p>We tried to make this package as modular as possible. This makes it
523easy to add new drivers, and unused drivers will take no precious kernel
524space. On the other hand, it can be a bit confusing at first.
525
526   <p>Here are two simple guidelines:
527     <ul>
528  <li>Run <span class="command">sensors-detect</span> and do what it tells you.
529  <li>Always use <span class="command">modprobe</span>, not <span class="command">insmod</span>.
530</ul>
531
532   <p>Further information is in <span class="file">doc/modules</span>.
533
534   <p><a name="How-do-I-know-which-chips-I-own"></a>
535<div class="node">
536<p><hr>
537<a name="Section-3_002e2"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e3">Section 3.3</a>,
538Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e1">Section 3.1</a>,
539Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
540<br>
541</div>
542
543<h3 class="section">3.2 How do I know which chips I own?</h3>
544
545<p>We have an excellent program that scans all your hardware.
546It is called <span class="file">sensors-detect</span> and is installed in <span class="file">/usr/local/sbin</span>
547by <span class="command">make install</span>. Just execute this script, and it will tell you.
548
549   <p>Chip detection in the drivers is fairly good. That means that it is
550usually harmless to insert more chip drivers than you need. However, this
551can still lead to problems, so we do not recommend it.
552
553   <p>If sensors-detect didn't find any sensors, either you don't have
554any, or the ones you have, we don't support. (Look at your motherboard
555for candidates, then see <a href="#Help">Help</a>)
556
557   <p><a name="Section-3_002e2_002e1"></a>
558
559<h4 class="subsection">3.2.1 What chips are on motherboard XYZ?</h4>
560
561<p><strong>!!!!!!!!! YES THIS IS THE MOST FREQUENT QUESTION WE GET !!!!!!!!!</strong>
562
563   <p>We have no idea. Here is what you should do:
564     <ol type=1 start=1>
565  <li>Run sensors-detect.
566        </ol>
567
568   <p>If that doesn't work:
569     <ol type=1 start=2>
570<li>Look at your motherboard.
571<li>Check the manufacturer's website or ask their support
572<li>Check the <a href="http://mbm.livewiredev.com/">Motherboard Monitor</a> website and the
573<a href="http://www2.lm-sensors.nu/~lm78/cvs/lm_sensors2/doc/useful_addresses.html">"links"</a>
574page on <a href="http://www2.lm-sensors.nu/~lm78/">our website</a> some good cross-references.
575        </ol>
576
577   <p><a name="Section-3_002e2_002e2"></a>
578
579<h4 class="subsection">3.2.2 Do you support motherboard XYZ?</h4>
580
581<p>We don't support boards, we support chips. See <a href="#Section-3_002e2_002e1">What chips are on motherboard XYZ</a>.
582
583   <p><a name="Section-3_002e2_002e3"></a>
584
585<h4 class="subsection">3.2.3 Do you support chip XYZ?</h4>
586
587<p>This we have good answers for.
588     <ul>
589<li>Sorted by Manufacturer:   <span class="file">README</span>
590<li>Sorted by Manufacturer:   <a href="http://www2.lm-sensors.nu/~lm78/supported.html">http://www2.lm-sensors.nu/~lm78/supported.html</a>
591<li>Sorted by Sensor Driver:  <span class="file">doc/chips/SUMMARY</span>
592<li>Newest Driver Status:     <a href="http://www2.lm-sensors.nu/~lm78/newdrivers.html">http://www2.lm-sensors.nu/~lm78/newdrivers.html</a>
593</ul>
594
595   <p><a name="Section-3_002e2_002e4"></a>
596
597<h4 class="subsection">3.2.4 Anybody working on a driver for chip XYZ?</h4>
598
599<p>Newest Driver Status: <a href="http://www2.lm-sensors.nu/~lm78/newdrivers.html">http://www2.lm-sensors.nu/~lm78/newdrivers.html</a>
600
601<div class="node">
602<p><hr>
603<a name="Section-3_002e3"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e4">Section 3.4</a>,
604Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e2">Section 3.2</a>,
605Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
606<br>
607</div>
608
609<h3 class="section">3.3 Which modules should I insert?</h3>
610
611<p><span class="command">sensors-detect</span> will tell you. Take the <span class="command">modprobe</span> lines it
612recommends and paste them into the appropriate <span class="file">/etc/rc.d/xxxx</span> file
613to be executed at startup.
614
615   <p>You need one module for each sensor chip and bus adapter you own;
616if there are sensor chips on the ISA bus, you also need <span class="file">i2c-isa.o</span>.
617for each type of chip you own. That's all. On my computer, I could use the
618following lines:
619     <ul>
620<li><span class="command">modprobe i2c-isa</span>
621<li><span class="command">modprobe i2c-piix4</span>
622<li><span class="command">modprobe lm78</span>
623<li><span class="command">modprobe lm75</span>
624<li><span class="command">modprobe i2c-dev</span>
625<li><span class="command">sensors -s</span>
626</ul>
627
628<div class="node">
629<p><hr>
630<a name="Section-3_002e4"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e5">Section 3.5</a>,
631Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e3">Section 3.3</a>,
632Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
633<br>
634</div>
635
636<h3 class="section">3.4 Do I need the configuration file <span class="file">/etc/sensors.conf</span>?</h3>
637
638<p>Yes, for any applications that use <span class="file">libsensors,</span> including the
639<span class="command">sensors</span> application included in our package.
640It tells libsensors how to translate the values the chip
641measures to real-world values. This is especially important for voltage
642inputs. The default configuration file should usually do the trick.
643It is automatically installed as <span class="file">/etc/sensors.conf</span>, but it will not
644overwrite any existing file with that name.
645
646   <p><a name="Section-3_002e4_002e1"></a>
647
648<h4 class="subsection">3.4.1 The labels for the voltage and temperature readings in <span class="command">sensors</span> are incorrect!</h4>
649
650<p>Every motherboard is different. You can customize the labels
651in the file <span class="file">/etc/sensors.conf</span>. That's why it exists!
652The default labelling (in <span class="file">lib/chips.c</span> and <span class="file">/etc/sensors.conf</span>) is just
653a template.
654
655   <p><a name="Section-3_002e4_002e2"></a>
656
657<h4 class="subsection">3.4.2 The min and max for the readings in <span class="command">sensors</span> are incorrect!</h4>
658
659<p>You can customize them in the file <span class="file">/etc/sensors.conf</span>. See above.
660
661   <p><a name="Section-3_002e4_002e3"></a>
662
663<h4 class="subsection">3.4.3 The min and max settings in <span class="file">/etc/sensors.conf</span> didn't take effect!</h4>
664
665<p>You forgot to run <span class="command">sensors -s</span>. See above.
666
667   <p><a name="Section-3_002e4_002e4"></a>
668
669<h4 class="subsection">3.4.4 One sensor isn't hooked up on my board!</h4>
670
671<p>Use an <span class="command">ignore</span> line in <span class="file">/etc/sensors.conf</span> so it isn't
672displayed in <span class="command">sensors</span>.
673
674   <p><a name="Section-3_002e4_002e5"></a>
675
676<h4 class="subsection">3.4.5 I need help with <span class="file">sensors.conf</span>!</h4>
677
678<p>There is detailed help at the top of that file.
679
680   <p><a name="Section-3_002e4_002e6"></a>
681
682<h4 class="subsection">3.4.6 Do you have a database of <span class="file">sensors.conf</span> entries for specific boards?</h4>
683
684<p>No. Good idea though. If you would like to set one up on your website
685send us mail and we will set up a link to it.
686
687<div class="node">
688<p><hr>
689<a name="Section-3_002e5"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e6">Section 3.6</a>,
690Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e4">Section 3.4</a>,
691Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
692<br>
693</div>
694
695<h3 class="section">3.5 What about the <span class="samp">No such file or directory</span> warnings when I compile?</h3>
696
697<p>Don't worry about them. The dependency files (which tell which
698files should be recompiled when certain files change) are created
699dynamically. They are not distributed with the package. The <span class="command">make</span> program
700notices they are not there, and warns about that - and the first thing
701it will do is generate them. So all is well.
702
703<div class="node">
704<p><hr>
705<a name="Section-3_002e6"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e7">Section 3.7</a>,
706Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e5">Section 3.5</a>,
707Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
708<br>
709</div>
710
711<h3 class="section">3.6 I get all kinds of weird compilation errors?</h3>
712
713<p>Check that the correct i2c header files are used. Depending on
714how you installed, they should be under either <span class="file">/usr/local/include</span> or
715<span class="file">/usr/src/linux*/include</span>. Try to edit the <span class="file">Makefile</span> for the other setting.
716
717   <p><a name="Section-3_002e6_002e1"></a>
718
719<h4 class="subsection">3.6.1 <span class="samp">No rule to make target xxxx needed by xxxx</span> - how to fix?</h4>
720
721     <ul>
722<li>See <a href="#Section-3_002e6">I get all kinds of weird compilation errors</a>, also try <span class="command">make clean</span> in <span class="file">lm_sensors</span>.
723<li>If that doesn't work, try <span class="command">make clean</span> in <span class="file">i2c</span>.
724<li>If that doesn't work, try <span class="command">make clean</span> in the kernel.
725<li>Also make sure <span class="file">/usr/include/linux</span> points to <span class="file">/usr/src/linux/include/linux</span>.
726</ul>
727
728<div class="node">
729<p><hr>
730<a name="Section-3_002e7"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e8">Section 3.8</a>,
731Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e6">Section 3.6</a>,
732Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
733<br>
734</div>
735
736<h3 class="section">3.7 It still does not compile or patch!</h3>
737
738<p>Have you installed the matching version of the i2c package? Remember,
739compilation is not enough, you also need to install it for the header
740files to be found!
741
742   <p>If you want to patch the kernel, you will have to apply the i2c
743patches first!
744
745<div class="node">
746<p><hr>
747<a name="Section-3_002e8"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e9">Section 3.9</a>,
748Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e7">Section 3.7</a>,
749Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
750<br>
751</div>
752
753<h3 class="section">3.8 <span class="command">make install</span> fails on Mandrake kernels</h3>
754
755<p>Mandrake uses a non-standard <span class="file">version.h</span> file which confuses our <span class="file">Makefile</span>.
756Edit our <span class="file">Makefile</span> on the <code>MODDIR :=</code> line to hard-code the module directory.
757
758<div class="node">
759<p><hr>
760<a name="Section-3_002e9"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-3_002e10">Section 3.10</a>,
761Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e8">Section 3.8</a>,
762Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
763<br>
764</div>
765
766<h3 class="section">3.9 I get unresolved symbols when I <span class="command">modprobe</span> modules (Red Hat especially)</h3>
767
768<p>Example:
769<pre class="example">     *** Unresolved symbols in /lib/modules/2.4.5/kernel/drivers/i2c/i2c-i810.o
770     i2c_bit_add_bus_R8c3bc60e
771     i2c_bit_del_bus_R92b18f49
772</pre>
773   <p>You can also run <span class="command">depmod -a -e</span> to see all unresolved symbols.
774
775   <p>These are module versioning problems. Generally you did not compile
776against the kernel you are running. Sometimes the Red Hat source you
777have is not for the kernel you are running.
778You must compile our package against the source for the kernel you
779are running with something like <span class="command">make LINUX=/usr/src/linux-2.4.14</span>.
780
781   <p>Try the following to be sure:
782
783     <ul>
784<li><span class="command">nm --extern MODULE.o</span>
785Filter out the kernel symbols, like <code>kmalloc</code>, <code>printk</code> etc. and note the
786number code behind them, like <code>printk_R1b7d4074</code>. If there is no numeric
787code after them, note this too.
788<li><span class="command">grep SYMBOL /proc/ksyms</span>
789Substitute SYMBOL by the basename of the symbols above, like <code>kmalloc</code>,
790<code>printk</code> etc. Note the number code behind them, or the lack thereof.
791<li>Compare both sets of symbols. Are they the same? If so, the problem
792lies somewhere else. Are they different? If so, you have a module
793versioning problem.
794</ul>
795
796<div class="node">
797<p><hr>
798<a name="Section-3_002e10"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-3_002e9">Section 3.9</a>,
799Up:&nbsp;<a rel="up" accesskey="u" href="#Installation">Installation</a>
800<br>
801</div>
802
803<h3 class="section">3.10 I2C_DRIVERID_ADM1024 undefined (Red Hat especially)</h3>
804
805<p>In some versions of Redhat, an RPM is included to provide i2c support.
806However, this RPM does not place the header files in the kernel directory
807structure.  When you update kernels, they may persist.  To get rid of
808these obsolete header files, at a command prompt:
809
810     <ol type=1 start=1>
811<li><span class="command">rpm -qa | grep i2c</span>
812<li>Look for <span class="file">kernel-i2c,</span> or a similar rpm in the output
813<li>&lt;as root&gt;
814<span class="command">rpm -ev kernel-i2c</span> (or the name of the similar package)
815If this complains about dependencies, you can try adding
816<span class="command">--nodeps</span>, but this *MAY* break something else.  Not likely,
817as you have upgraded kernels, and nothing should be using the
818old i2c stuff anymore anyway.  Just don't use it with abandon.
819<li>Try (in the build directory of <span class="file">lm_sensors)</span>
820     <pre class="example">          <span class="command">make clean</span>
821          <span class="command">make</span>
822     </pre>
823     <li><em>If</em> you still have problems, you may have to replace the include
824paths in the <span class="file">.c/.h</span> files with absolute paths to the header files.
825More of a workaround than a real fix, but at least you can get it
826to work.
827        </ol>
828
829<div class="node">
830<p><hr>
831<a name="Problems"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Help">Help</a>,
832Previous:&nbsp;<a rel="previous" accesskey="p" href="#Installation">Installation</a>,
833Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
834<br>
835</div>
836
837<h2 class="chapter">4 Problems</h2>
838
839<ul class="menu">
840<li><a accesskey="1" href="#Section-4_002e1">Section 4.1</a>:          My fans report exactly half/double their values?
841<li><a accesskey="2" href="#Section-4_002e2">Section 4.2</a>:          Why do my two LM75's report "-48 degrees"?
842<li><a accesskey="3" href="#Section-4_002e3">Section 4.3</a>:          Why do I have two Vcore readings?
843<li><a accesskey="4" href="#Section-4_002e4">Section 4.4</a>:          How do those ALARMS work?
844<li><a accesskey="5" href="#Section-4_002e5">Section 4.5</a>:          My voltage readings seem to drift a bit. What's wrong?
845<li><a accesskey="6" href="#Section-4_002e6">Section 4.6</a>:          Some measurements are way out of range. What happened?
846<li><a accesskey="7" href="#Section-4_002e7">Section 4.7</a>:          What are VID lines? Why is the VID reading wrong?
847<li><a accesskey="8" href="#Section-4_002e8">Section 4.8</a>:          Sensor are only updated each second or so. Why?
848<li><a accesskey="9" href="#Section-4_002e9">Section 4.9</a>:          It takes a second before reading sensor results. Why?
849<li><a href="#Section-4_002e10">Section 4.10</a>:         Can I be alerted when an ALARM occurs?
850<li><a href="#Section-4_002e11">Section 4.11</a>:         SMBus transactions on my PIIX4 simply don't work. Why?
851<li><a href="#Section-4_002e12">Section 4.12</a>:         My BIOS reports a higher CPU temperature than you!
852<li><a href="#Section-4_002e13">Section 4.13</a>:         I read strange values from the raw <span class="file">/proc</span> files!
853<li><a href="#Section-4_002e14">Section 4.14</a>:         How do I set new limits?
854<li><a href="#Section-4_002e15">Section 4.15</a>:         Some sensors are doubly detected?
855<li><a href="#Section-4_002e16">Section 4.16</a>:         I ran sensors-detect, but now I get strange readings?!
856<li><a href="#Section-4_002e17">Section 4.17</a>:         Bad readings from particular chips
857<li><a href="#Section-4_002e18">Section 4.18</a>:         How do I configure two chips (LM87) differently?
858<li><a href="#Section-4_002e19">Section 4.19</a>:         Dmesg says <span class="samp">Upgrade BIOS</span>! I don't want to!
859<li><a href="#Section-4_002e20">Section 4.20</a>:         Sensors says <span class="samp">Can't access procfs/sysfs file</span>
860<li><a href="#Section-4_002e21">Section 4.21</a>:         Sensors says <span class="samp">No sensors found!</span>
861<li><a href="#Section-4_002e22">Section 4.22</a>:         Sensors output is not correct!
862<li><a href="#Section-4_002e23">Section 4.23</a>:         What is at I2C address XXX?
863<li><a href="#Section-4_002e24">Section 4.24</a>:         Sensors-detect doesn't work at all
864<li><a href="#Section-4_002e25">Section 4.25</a>:         Sensors says <span class="samp">Error: Line xxx: zzzzzzz</span>
865<li><a href="#Section-4_002e26">Section 4.26</a>:         Sensors only gives the name, adapter, and algorithm!
866<li><a href="#Section-4_002e27">Section 4.27</a>:         Sensors says <span class="samp">ERROR: Can't get xxxxx data!</span>
867<li><a href="#Section-4_002e28">Section 4.28</a>:         Sensors doesn't find any sensors, just eeproms.
868<li><a href="#Section-4_002e29">Section 4.29</a>:         Inserting modules hangs my board
869<li><a href="#Section-4_002e30">Section 4.30</a>:         Inserting modules slows down my board
870<li><a href="#Section-4_002e31">Section 4.31</a>:         Problems on particular motherboards
871<li><a href="#Section-4_002e32">Section 4.32</a>:         Problems on particular systems
872<li><a href="#Section-4_002e33">Section 4.33</a>:         Problems on 2.6 kernels
873</ul>
874
875<div class="node">
876<p><hr>
877<a name="Section-4_002e1"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e2">Section 4.2</a>,
878Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
879<br>
880</div>
881
882<h3 class="section">4.1 My fans report exactly half/double their values compared to the BIOS?</h3>
883
884<p>The problem with much of the sensor data is that it is impossible to
885properly interpret some of the readings without knowing what the hardware
886configuration is.  Some fans report one 'tick' each rotation, some report
887two 'ticks' each rotation. It is easy to resolve this through the
888configuration file <span class="file">/etc/sensors.conf</span>:
889
890<pre class="example">     chip lm78-*             # Or whatever chip this relates to
891     compute fan1 2*@,@/2    # This will double the fan1 reading
892                             # -- or --
893     compute fan1 @/2,2*@    # This will halve the fan1 reading
894</pre>
895   <p>See <span class="file">doc/fan-divisors</span> in our package for further information.
896
897   <p><a name="Fans-sometimes_002falways-read-0_0021"></a>
898
899<h4 class="subsection">4.1.1 Fans sometimes/always read 0!!</h4>
900
901<p>You may not have a three-wire fan, which is required.
902
903   <p>You may need to increase the 'fan divisor'. See <span class="file">doc/fan-divisors</span>
904in our package for further information.
905
906   <p><a name="I-doubled-the-fan-divisor-and-the-fan-still-reads-7000"></a>
907
908<h4 class="subsection">4.1.2 I doubled the fan divisor and the fan still reads 7000!</h4>
909
910<p>Believe it or not, doubling the 'fan divisor' will not halve
911the fan reading. You have to add a compute line in <span class="file">/etc/sensors.conf</span>.
912See <a href="#Section-4_002e1">My fans report exactly half/double their values compared to the BIOS</a>,
913and see <span class="file">doc/fan-divisors</span> in our package for further information.
914
915<div class="node">
916<p><hr>
917<a name="Section-4_002e2"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e3">Section 4.3</a>,
918Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e1">Section 4.1</a>,
919Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
920<br>
921</div>
922
923<h3 class="section">4.2 Why do my two LM75's report "-48 degrees"?</h3>
924
925<p>For starters, those aren't LM75's.  Your mainboard actually has the
926Winbond W83781D which emulates two LM75's, but many systems which use the
927Winbond chip (such as the Asus P2B) don't have the thermo-resisters connected
928to the chip resulting in these strange -48 degree readings.
929
930   <p>In upcoming versions, you will be able to disable non-interesting
931readings.
932
933<div class="node">
934<p><hr>
935<a name="Section-4_002e3"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e4">Section 4.4</a>,
936Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e2">Section 4.2</a>,
937Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
938<br>
939</div>
940
941<h3 class="section">4.3 Why do I have two Vcore readings, I have only one processor!</h3>
942
943<p>The LM78 has seven voltage sensors. The default way of
944connecting them is used in the configuration file. This includes a VCore2,
945even if you do not have one. You can easily edit the configuration file
946to give it another name, or make this reading disappear using
947an <span class="command">ignore</span> line.
948
949   <p>Note that Vcore2 is often the same as Vcore on motherboards which
950only support one processor. Another possibility is that Vcore2 is not
951connected at all and will not have a valid reading at all.
952A third possibility, is that Vcore2 monitors something
953else, so you should not be too surprised if the values are completely
954different.
955
956<div class="node">
957<p><hr>
958<a name="Section-4_002e4"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e5">Section 4.5</a>,
959Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e3">Section 4.3</a>,
960Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
961<br>
962</div>
963
964<h3 class="section">4.4 How do those ALARMS work? The current value is within range but there is still an ALARM warning!</h3>
965
966<p>The ALARM indications in <span class="command">sensors</span> are those reported by the
967sensor chip itself. They are NOT calculated by <span class="command">sensors</span>. <span class="command">sensors</span>
968simply reads the ALARM bits and reports them.
969
970   <p>An ALARM will go off when a minimum or maximum limit is crossed.
971The ALARM is then latched - that is, it will stay there until the
972chip's registers are next accessed - which will be the next time
973you read these values, but not within (usually) 1.5 seconds since the last
974update.
975
976   <p>Reading the registers clears the ALARMS, unless the current
977value is still out of range.
978
979   <p>The purpose of this scheme is to tell you if there has been
980a problem and report it to the user. Voltage or temperature spikes
981get detected without having to read the sensor chip hundreds of times
982a second. The implemetation details depend a bit on the kind of chip.
983See the specific chip documentation in <span class="file">doc/chips</span> and the
984chip datasheet for more information.
985
986<div class="node">
987<p><hr>
988<a name="Section-4_002e5"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e6">Section 4.6</a>,
989Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e4">Section 4.4</a>,
990Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
991<br>
992</div>
993
994<h3 class="section">4.5 My voltage readings seem to drift a bit. Is something wrong?</h3>
995
996<p>No, probably not. If your motherboard heats up a bit, the sensed
997voltages will drift a bit. If your power supply is loaded (because a disk
998gets going, for example), the voltages may get a bit lower. Heavy
999processor activity, in particular, dramatically increases core voltage
1000supply load which will often cause variation in the other supplies.
1001As long as they stay within a sensible range (say 5% of the nominal value
1002for CPU core voltages, and 10% for other voltages), there is no
1003reason to worry.
1004
1005<div class="node">
1006<p><hr>
1007<a name="Section-4_002e6"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e7">Section 4.7</a>,
1008Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e5">Section 4.5</a>,
1009Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1010<br>
1011</div>
1012
1013<h3 class="section">4.6 Some measurements are way out of range. What happened?</h3>
1014
1015<p>Each module tries to set limits to sensible values on initialization,
1016but a module does not know how a chip is actually connected. This is
1017described in the configuration file, which is not read by kernel modules.
1018So limits can be strange, if the chip is connected in a non-standard way.
1019
1020   <p>Readings can also be strange; there are several reasons for this.
1021Temperature sensors, for example, can simply not be present, even though
1022the chip supports them. Also, it can be that the input is used in a
1023non-standard way. You can use the configuration file to describe how this
1024measurement should be interpreted; see the comments the example file for
1025more information.
1026
1027   <p><a name="_002d5V-and-_002d12V-readings-are-way-out-of-range_0021"></a>
1028
1029<h4 class="subsection">4.6.1 -5V and -12V readings are way out of range!</h4>
1030
1031<p>It's very frequent that negative voltage lines are not wired because
1032motherboard manufacturers don't think they're worth monitoring
1033(they are mostly unused these days). You can just add
1034<span class="command">ignore inN</span> lines to <span class="file">/etc/sensors.conf</span> to hide them.
1035
1036<div class="node">
1037<p><hr>
1038<a name="Section-4_002e7"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e8">Section 4.8</a>,
1039Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e6">Section 4.6</a>,
1040Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1041<br>
1042</div>
1043
1044<h3 class="section">4.7 What are VID lines? Why is the VID reading wrong?</h3>
1045
1046<p>These describe the core voltage for your processor. They are
1047supported for most processors, however they are not always
1048correctly connected to the sensor chip, so the readings may be invalid.
1049A reading of 0V, +3.5V or +2.05V is especially suspect.
1050If this is the case, add a line <span class="command">ignore vid</span> to <span class="file">/etc/sensors.conf</span>,
1051and change the min and max settings for the Processor Core voltage
1052(often in0_min and in0_max) in that file so that they don't depend on vid.
1053
1054   <p>The CPU nominal voltage is computed from VID lines according to a formula
1055that depends on the CPU type. Most chips that report a VID value can be
1056configured to use either VRM 8.2 (for Pentium III) or VRM 9.0 (for Pentium 4
1057and Athlon). You chose which one you want through <span class="file">/etc/sensors.conf</span>.
1058See <span class="file">doc/vid</span> for more information.
1059
1060<div class="node">
1061<p><hr>
1062<a name="Section-4_002e8"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e9">Section 4.9</a>,
1063Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e7">Section 4.7</a>,
1064Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1065<br>
1066</div>
1067
1068<h3 class="section">4.8 I read sensor values several times a second, but they are only updated only each second or so. Why?</h3>
1069
1070<p>If we would read the registers more often, it would not find the
1071time to update them. So we only update our readings once each 1.5 seconds
1072(the actual delay is chip-specific; for some chips, it may not be needed
1073at all).
1074
1075<div class="node">
1076<p><hr>
1077<a name="Section-4_002e9"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e10">Section 4.10</a>,
1078Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e8">Section 4.8</a>,
1079Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1080<br>
1081</div>
1082
1083<h3 class="section">4.9 It sometimes seems to take almost a second before I see the sensor reading results. Why?</h3>
1084
1085<p>ISA bus access is fast, but SMBus access is really slow. If you have
1086a lot of sensors, it just takes a lot of time to access them. Fortunately,
1087this has almost no impact on the system as a whole, as another job can run
1088while we are waiting for the transaction to finish.
1089
1090<div class="node">
1091<p><hr>
1092<a name="Section-4_002e10"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e11">Section 4.11</a>,
1093Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e9">Section 4.9</a>,
1094Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1095<br>
1096</div>
1097
1098<h3 class="section">4.10 Can I be alerted when an ALARM occurs?</h3>
1099
1100<p>No, you can't; and it may well be never supported.
1101
1102   <p>Almost no mainboard we have encountered have actually connected the
1103IRQ-out pin of sensor chips. That means that we could enable IRQ reporting, but
1104nothing would happen. Also, even if a motherboard has it connected, it is
1105unclear what interrupt number would be triggered. And IRQ lines are a scarce
1106facility, which means that almost nobody would be able to use it anyway.
1107
1108   <p>The SMI interrupt is only available on a few types of chips. It is
1109really a very obscure way to handle interrupts, and supporting it under Linux
1110might be quite hard to do.
1111
1112   <p>Your best bet would be to poll the alarm file with a user-land daemon
1113which alerts you if an alarm is raised. I am not aware of any program which
1114does the job, though you might want to examine one of the graphical monitor
1115programs under X, see <a href="http://www2.lm-sensors.nu/~lm78/useful_addresses.html">http://www2.lm-sensors.nu/~lm78/useful_addresses.html</a> for addresses.
1116
1117<div class="node">
1118<p><hr>
1119<a name="Section-4_002e11"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e12">Section 4.12</a>,
1120Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e10">Section 4.10</a>,
1121Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1122<br>
1123</div>
1124
1125<h3 class="section">4.11 SMBus transactions on my PIIX4 simply don't work (timeouts happen).  Why?</h3>
1126
1127<p>Some chips which mainboard makers connect to the SMBus are not SMBus
1128devices.  An example is the 91xx clock generator chips.  When read, these
1129devices can lock up the SMBus until the next hard reboot.  This is because
1130they have a similar serial interface (like the I2C), but don't conform to
1131Intel's SMBus standard.
1132
1133   <p>Why did they connect these devices to the SMBus if they aren't
1134compatible?  Good question! :')  Actually, these devices may support being
1135written to, but lock things up when they are read.
1136
1137<div class="node">
1138<p><hr>
1139<a name="Section-4_002e12"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e13">Section 4.13</a>,
1140Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e11">Section 4.11</a>,
1141Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1142<br>
1143</div>
1144
1145<h3 class="section">4.12 My BIOS reports a much higher CPU temperature than your modules!</h3>
1146
1147<p>We display the actual temperature of the sensor. This may not be the
1148temperature you are interested in, though.  If a sensor should measure
1149the CPU temperature, it must be in thermal contact with it.  In practice,
1150it may be just somewhere nearby. Your BIOS may correct for this (by adding,
1151for example, thirty degrees to the measured temperature).  The correction
1152factor is regrettably different for each mainboard, so we can not do this
1153in the module itself. You can do it through the configuration file, though:
1154
1155<pre class="example">     chip lm75-*-49                      # Or whatever chip this relates to
1156     label temp "Processor"
1157     compute temp @*1.2+13,(@-13)/1.2    # Or whatever formula
1158</pre>
1159   <p>However, the offset you are introducing might not be necessary. If you
1160tried to have Linux idle temperature and BIOS "idle" temperature match,
1161you may be misguided.
1162We have a Supermicro (370DLE) motherboard and we know
1163that its BIOS has a closed, almost undelayed while(1) loop that
1164keeps the CPU busy all the time. Linux reads 26 degrees idle, BIOS reads
116538 degrees. Linux at full load is in the 35-40 degrees range so this
1166makes sense.
1167
1168<div class="node">
1169<p><hr>
1170<a name="Section-4_002e13"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e14">Section 4.14</a>,
1171Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e12">Section 4.12</a>,
1172Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1173<br>
1174</div>
1175
1176<h3 class="section">4.13 I try to read the raw <span class="file">/proc</span> files, but the values are strange?!?</h3>
1177
1178<p>Remember, these values do not take the configuration file
1179<span class="file">compute</span> lines in account. This is especially obvious for voltage readings
1180(usually called in? or vin?). Use a program linked to libsensors (like
1181the provided <span class="command">sensors</span> program) instead.
1182
1183<div class="node">
1184<p><hr>
1185<a name="Section-4_002e14"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e15">Section 4.15</a>,
1186Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e13">Section 4.13</a>,
1187Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1188<br>
1189</div>
1190
1191<h3 class="section">4.14 How do I set new limits?</h3>
1192
1193<p>Change the limit values in <span class="file">/etc/sensors.conf</span> and then run
1194<span class="command">sensors -s</span>.
1195
1196   <p><a name="I-set-new-limits-and-it-didnt-work"></a>
1197
1198<h4 class="subsection">4.14.1 I set new limits and it didn't work?</h4>
1199
1200<p>You forgot to run <span class="command">sensors -s</span>. Put it in a <span class="file">/etc/rc.d/...</span> file
1201after the modprobe lines to run at startup.
1202
1203<div class="node">
1204<p><hr>
1205<a name="Section-4_002e15"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e16">Section 4.16</a>,
1206Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e14">Section 4.14</a>,
1207Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1208<br>
1209</div>
1210
1211<h3 class="section">4.15 Some sensors are doubly detected?</h3>
1212
1213<p>Yes, this is still a problem. It is partially solved by alias detection
1214and confidence values in sensors-detect, but it is really tough.
1215
1216   <p>Double detections can be caused by two things:
1217sensors can be detected to both the ISA and the SMBus (and if you have
1218loaded the approprate adapter drivers, it will be detected on both), and
1219some chips simulate other chips (the Winbond W83781D simulates LM75 chips
1220on the SMBus, for example). Remove the offending adapter or chip driver, or
1221run sensors-detect and add the <span class="command">ignore=</span> modprobe parameters it suggests.
1222
1223<div class="node">
1224<p><hr>
1225<a name="Section-4_002e16"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e17">Section 4.17</a>,
1226Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e15">Section 4.15</a>,
1227Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1228<br>
1229</div>
1230
1231<h3 class="section">4.16 I ran sensors-detect, but now I get very strange readings?!?</h3>
1232
1233<p>Your SMBus (PIIX4?) is probably crashed or hung. There are some mainboards
1234which connect a clock chip to the SMBus. Unfortunately, this clock chip
1235hangs the PIIX4 if it is read (it is an I2C device, but not SMBus compatible).
1236We have found no way of solving this, except for rebooting your computer.
1237Next time when you run sensors-detect, you may want to exclude addresses
12380x69 and/or 0x6a, by entering <kbd>s</kbd> when you are asked whether you want to
1239scan the PIIX4.
1240
1241<div class="node">
1242<p><hr>
1243<a name="Section-4_002e17"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e18">Section 4.18</a>,
1244Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e16">Section 4.16</a>,
1245Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1246<br>
1247</div>
1248
1249<h3 class="section">4.17 Bad readings from particular chips</h3>
1250
1251<p>See below for some particularly troublesome chips.
1252Also be sure and check <span class="file">doc/chips/xxxxx</span> for the particular driver.
1253
1254   <p><a name="Bad-readings-from-the-AS99127F"></a>
1255
1256<h4 class="subsection">4.17.1 Bad readings from the AS99127F!</h4>
1257
1258<p>The Asus AS99127F is a modified version of the Winbond W83781D.
1259Asus will not release a datasheet. The driver was developed by tedious
1260experimentation. We've done the best we can. If you want to make adjustments
1261to the readings please edit <span class="file">/etc/sensors.conf.</span> Please don't ask us to
1262fix the driver. Ask Asus to release a datasheet.
1263
1264   <p><a name="Bad-readings-from-the-VIA-686A"></a>
1265
1266<h4 class="subsection">4.17.2 Bad readings from the VIA 686A!</h4>
1267
1268<p>The Via 686A datasheet is incomplete.
1269Via will not release details. The driver was developed by tedious
1270experimentation. We've done the best we can. If you want to make adjustments
1271to the readings please edit <span class="file">/etc/sensors.conf.</span> Please don't ask us to
1272fix the driver. Ask Via to release a better datasheet.
1273Also, don't forget to <span class="command">modprobe i2c-isa</span>.
1274
1275   <p><a name="Bad-readings-from-the-MTP008"></a>
1276
1277<h4 class="subsection">4.17.3 Bad readings from the MTP008!</h4>
1278
1279<p>The MTP008 has programmable temperature sensor types.
1280If your sensor type does not match the default, you will have to change it.
1281See <span class="file">doc/chips/mtp008</span> for details.
1282Also, MTP008 chips seem to randomly refuse to respond, for
1283unknown reasons. You can see this as 'XX' entries in i2cdump.
1284
1285   <p><a name="Bad-temperature-readings-from-the-SIS5595"></a>
1286
1287<h4 class="subsection">4.17.4 Bad temperature readings from the SIS5595!</h4>
1288
1289<p>This chip can use multiple thermistor types and there are also
1290two different versions of the chip. We are trying to get the driver
1291working better and develop formulas for different thermistors
1292but we aren't there yet. Sorry.
1293Also, many times the chip isn't really a sis5595 but it was
1294misidentified. We are working on improving that too.
1295
1296   <p><a name="Bad-readings-from-a-w8378_005b12_005dd"></a>
1297
1298<h4 class="subsection">4.17.5 Bad readings from a w8378[12]d!</h4>
1299
1300<p>Do you own an ASUS motherboard?  Perhaps your chip is being
1301misidentified.  Look on the motherboard (or at
1302<a href="http://mbm.livewiredev.com">http://mbm.livewiredev.com</a>) for a 'Winbond' or Asus chip.
1303Often the real device is an Asus as99127f. If so, the driver can be
1304forced to recognize the as99127f with
1305<span class="command">force_as99127f=BUS,0x2d</span> where <code>BUS</code> is your i2c bus number.
1306Cat /proc/bus/i2c to see a list of bus numbers.
1307Read the w83781d module documentation (<span class="file">doc/chips/w83781d</span>)
1308for more details.
1309
1310   <p><a name="Bus-hangs-on-Ali-1543-on-Asus-P5A-boards"></a>
1311
1312<h4 class="subsection">4.17.6 Bus hangs on Ali 1543 on Asus P5A boards!</h4>
1313
1314<p>The SMBus tends to hang on this board and it seems to get worse
1315at higher temperatures. Use ISA accesses to reliably use the w83781d
1316monitor chip on this board and use the <span class="command">ignore=1,0x2d</span> or similar option
1317to the w83781d module to prevent i2c accesses.
1318
1319   <p><a name="Bad-readings-from-LM75"></a>
1320
1321<h4 class="subsection">4.17.7 Bad readings from LM75!</h4>
1322
1323<p>The LM75 detection is poor and other hardware is often misdetected
1324as an LM75. Figure out what you really have See <a href="#Section-3_002e2_002e1">What chips are on motherboard XYZ</a>.
1325
1326   <p><a name="Bad-readings-from-LM78"></a>
1327
1328<h4 class="subsection">4.17.8 Bad readings from LM78!</h4>
1329
1330<p>The LM78 is no longer manufactured by National Semiconductor.
1331You probably don't have a real LM78 but something similar that we
1332do not recogize or support. Figure out what you really have See <a href="#Section-3_002e2_002e1">What chips are on motherboard XYZ</a>.
1333
1334   <p><a name="Bad-readings-from-LM80"></a>
1335
1336<h4 class="subsection">4.17.9 Bad readings from LM80!</h4>
1337
1338<p>The LM80 detection is poor and other hardware is often misdetected
1339as an LM80. Figure out what you really have See <a href="#Section-3_002e2_002e1">What chips are on motherboard XYZ</a>.
1340
1341   <p><a name="Bad-readings-from-it87"></a>
1342
1343<h4 class="subsection">4.17.10 Bad readings from it87!</h4>
1344
1345<p>The it87 temperature sesnsors are configured, unfortunately,
1346in a way different from w83781d. They cannot be configured from
1347<span class="file">/etc/sensors.conf</span>; they must be set at modprobe insertion with
1348<span class="command">modprobe it87 temp_type=0xXX</span>. See <span class="file">doc/chips/it87</span> for details.
1349
1350<div class="node">
1351<p><hr>
1352<a name="Section-4_002e18"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e19">Section 4.19</a>,
1353Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e17">Section 4.17</a>,
1354Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1355<br>
1356</div>
1357
1358<h3 class="section">4.18 How do I configure two chips (LM87) differently?</h3>
1359
1360<p>There is a SuperMicro board with two LM87's on it that are
1361not hooked up in the same way, so they need different defaults.
1362For example, both CPU temperatures go to one LM87.
1363
1364   <p>Make two different sections in <span class="file">/etc/sensors.conf</span> as follows:
1365<pre class="example">     chip "lm87-i2c-*-2c"
1366         put configuration for the chip at 0x2c here
1367     chip "lm87-i2c-*-2d"
1368         put configuration for the chip at 0x2d here
1369</pre>
1370   <p>There is a commented example in <span class="file">sensors.conf.eg</span> which should
1371be helpful.
1372
1373<div class="node">
1374<p><hr>
1375<a name="Section-4_002e19"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e20">Section 4.20</a>,
1376Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e18">Section 4.18</a>,
1377Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1378<br>
1379</div>
1380
1381<h3 class="section">4.19 Dmesg says <span class="samp">Upgrade BIOS</span>! I don't want to!</h3>
1382
1383<p>If the problem is a PCI device is not present in <span class="command">lspci</span>, the solution
1384is complex. For the ALI M7101 device, there is a solution which uses the
13852.4 kernel's <span class="command">hotplug</span> facility. See <span class="file">prog/hotplug</span> in our package.
1386For other PCI devices, you can try to modify
1387the m7101 solution in <span class="file">prog/hotplug</span>.
1388
1389   <p>If dmesg says <span class="samp">try force_addr</span>, see below. Other drivers generally do not
1390support the force_addr parameter. Sorry. Check the documentation
1391for your driver in <span class="file">doc/[chips,busses]</span> and if we don't support it
1392you can send us your request.
1393
1394   <p><a name="Dmesg-says-use-force_005faddr_003d0xaddr_0021-What-address-do-I-use"></a>
1395
1396<h4 class="subsection">4.19.1 Dmesg says <span class="samp">use force_addr=0xaddr</span>! What address do I use?</h4>
1397
1398<p>If the problem is a PCI device whose base address is not set,
1399you may be able to set the address with a force parameter. The via686a
1400and sis5595 chip drivers, and some bus drivers, support the command line
1401<span class="command">modprobe via686a force_addr=0xADDRESS</span> where ADDRESS
1402is the I/O address. You must select an address that is not in use.
1403<span class="command">cat /proc/ioports</span> to check (carefully) for conflicts. A high number like
14040xf000 is generally safe.
1405
1406<div class="node">
1407<p><hr>
1408<a name="Section-4_002e20"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e21">Section 4.21</a>,
1409Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e19">Section 4.19</a>,
1410Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1411<br>
1412</div>
1413
1414<h3 class="section">4.20 Sensors says <span class="samp">Can't access procfs/sysfs file</span></h3>
1415
1416     <ul>
1417<li>Linux 2.6
1418          <ul>
1419<li>Did you <span class="command">modprobe i2c_sensor</span>? Check <span class="command">lsmod</span>.
1420<li>Do you have sysfs support in your kernel and <span class="file">/sys</span> mounted (is <span class="file">/sys</span> there and populated)?
1421Create /sys with <span class="command">mkdir /sys</span> if needed. Then add the following line to <span class="file">/etc/fstab</span>:
1422          <pre class="example">               sys              /sys             sysfs       default          0   0</pre>
1423          <p>and <span class="command">mount /sys</span>.
1424</ul>
1425     <li>Linux 2.4
1426          <ul>
1427<li>Did you <span class="command">modprobe i2c-proc</span>? Check <span class="command">lsmod</span>.
1428<li>Do you have procfs support in your kernel and <span class="file">/proc</span> mounted (is <span class="file">/proc</span> there and populated)?
1429Create /proc with <span class="command">mkdir /proc</span> if needed. Then add the following line to <span class="file">/etc/fstab</span>:
1430          <pre class="example">               proc             /proc            proc        defaults         0   0</pre>
1431          <p>and <span class="command">mount /proc</span>.
1432</ul>
1433     <li>If you did <span class="command">sensors -s</span>, did you run it as root?
1434</ul>
1435
1436<div class="node">
1437<p><hr>
1438<a name="Section-4_002e21"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e22">Section 4.22</a>,
1439Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e20">Section 4.20</a>,
1440Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1441<br>
1442</div>
1443
1444<h3 class="section">4.21 Sensors says <span class="samp">No sensors found!</span></h3>
1445
1446     <ul>
1447<li>Did <span class="command">sensors-detect</span> find sensors? (If not see <a href="#Sensors_002ddetect-doesnt-find-any-sensors">Sensors-detect doesnt find any sensors</a>)
1448<li>Did you do what <span class="command">sensors-detect</span> said?
1449<li>Did you <span class="command">modprobe</span> your sensor modules?
1450<li>Did you <span class="command">modprobe</span> your I2C adapter modules?
1451<li>Did you <span class="command">modprobe i2c-isa</span> if you have ISA sensor chips?
1452<li>Check <span class="command">lsmod</span>.
1453</ul>
1454
1455<div class="node">
1456<p><hr>
1457<a name="Section-4_002e22"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e23">Section 4.23</a>,
1458Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e21">Section 4.21</a>,
1459Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1460<br>
1461</div>
1462
1463<h3 class="section">4.22 Sensors output is not correct!</h3>
1464
1465<p>What specifically is the trouble?
1466     <ul>
1467<li>Labels: See <a href="#Section-3_002e4_002e1">The labels for the voltage and temperature readings in sensors are incorrect</a>.
1468<li>Min/max readings: See <a href="#Section-3_002e4_002e2">The min and max for the readings in sensors are incorrect</a>, and See <a href="#Section-3_002e4_002e3">The min and max settings didnt take effect</a>.
1469<li>AS99127F: See <a href="#Section-4_002e16">I ran sensors-detect but now I get very strange readings?</a>.
1470<li>Via 686A: See <a href="#Section-4_002e16">I ran sensors-detect but now I get very strange readings?</a>.
1471<li>Other specific chips: See <a href="#Section-4_002e16">I ran sensors-detect but now I get very strange readings?</a>.
1472<li>No output for a particular sensors chip: See <a href="#Section-5_002e3">What to do if it inserts but nothing happens</a>.
1473<li>No output at all: See <a href="#Section-4_002e21">Sensors says No sensors found</a>, See <a href="#Section-5_002e3">What to do if it inserts but nothing happens</a>.
1474<li>Completely bad output for a particular sensor chip: See <a href="#Section-5_002e4">What to do if I read only bogus information</a>.
1475<li>One particular sensor readings:
1476          <ul>
1477<li>Maybe it isn't hooked up? - tell 'sensors' to ignore it. See <a href="#Section-3_002e4_002e4">One sensor isnt hooked up on my board</a>.
1478<li>Maybe it is hooked up differently on your motherboard? - adjust <span class="file">sensors.conf</span> calculation.
1479</ul>
1480     </ul>
1481
1482<div class="node">
1483<p><hr>
1484<a name="Section-4_002e23"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e24">Section 4.24</a>,
1485Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e22">Section 4.22</a>,
1486Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1487<br>
1488</div>
1489
1490<h3 class="section">4.23 What is at I2C address XXX?</h3>
1491
1492<p>In general, we don't know. Start by running <span class="command">sensors-detect</span>.
1493If it doesn't recognize it, try running <span class="command">i2cdump</span>. A partial list
1494of manufacturers' IDs are at the bottom of <span class="file">doc/chips/SUMMARY</span>.
1495
1496   <p><a name="What-is-at-I2C-address-0x69"></a>
1497
1498<h4 class="subsection">4.23.1 What is at I2C address 0x69?</h4>
1499
1500<p>A clock chip. Often, accessing these clock chips in the wrong
1501way will instantly crash your computer. Sensors-detect carefully
1502avoids these chips. If you really really want to play with your clock
1503chip you can look at <span class="file">kernel/chips/icspll.c</span> in our package. But we
1504do not recommend it. You have been warned.
1505
1506   <p><a name="What-is-at-I2C-addresses-0x50-_002d-0x57"></a>
1507
1508<h4 class="subsection">4.23.2 What is at I2C addresses 0x50 - 0x57?</h4>
1509
1510<p>EEPROMs on your SDRAM DIMMs. Load the eeprom module to
1511look at some basic data in <span class="command">sensors</span> or use the program
1512<span class="command">prog/eeprom/decode-dimms.pl</span> to get more information than you ever wanted.
1513
1514   <p><a name="What-is-at-I2C-addresses-0x30-_002d-0x37"></a>
1515
1516<h4 class="subsection">4.23.3 What is at I2C addresses 0x30 - 0x37?</h4>
1517
1518<p>These are often 'shadows' of your EEPROMs on your SDRAM DIMMs
1519at addresses 0x50 - 0x57. They are the 'software write-protect'
1520registers of the SDRAM Serial Presence Detect EEPROMs.
1521If you try and
1522do a <span class="command">i2cdump</span> on them to read the location, you won't get anything,
1523because they contain a single write-only register.
1524This register can be used to permanently
1525write-protect the contents of the eeprom.
1526
1527<div class="node">
1528<p><hr>
1529<a name="Section-4_002e24"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e25">Section 4.25</a>,
1530Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e23">Section 4.23</a>,
1531Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1532<br>
1533</div>
1534
1535<h3 class="section">4.24 Sensors-detect doesn't work at all</h3>
1536
1537<p>It could be many things. What was the problem? See <a href="#Section-4_002e31">Problems on particular motherboards</a>.
1538
1539   <p><a name="Sensors_002ddetect-says-_0022Couldnt-open-_002fproc_002fbus_002fi2c_003f_0021_003f_0022"></a>
1540
1541<h4 class="subsection">4.24.1 Sensors-detect says "Couldn't open /proc/bus/i2c?!?"</h4>
1542
1543<p>You don't have i2c support in your kernel, or the i2c-core module
1544was not loaded and you did not run sensors-detect as root.
1545
1546   <p><a name="Sensors_002ddetect-says-_0022Cant-open-_002fdev_002fi2c_005b_002d_002f_005d0_0022"></a>
1547
1548<h4 class="subsection">4.24.2 Sensors-detect says "Can't open /dev/i2c[-/]0"</h4>
1549
1550<p>Your <span class="file">/dev/i2c-0,</span> <span class="file">/dev/i2c0</span>, or <span class="file">/dev/i2c/0</span> files do not exist
1551or you did not run <span class="command">sensors-detect</span> as root.
1552Run the script <span class="command">prog/mkdev/mkdev.sh</span> to create the <span class="file">/dev/i2c-x</span> files.
1553Run <span class="command">devfs</span> in the kernel to get the <span class="file">/dev/i2c/x</span> files.
1554
1555   <p><a name="Sensors_002ddetect-doesnt-find-any-sensors"></a>
1556
1557<h4 class="subsection">4.24.3 Sensors-detect doesn't find any sensors!</h4>
1558
1559<p>Either
1560     <ol type=1 start=1>
1561<li>The board doesn't have any sensors.
1562<li>We don't support the sensors on the board.
1563<li>The sensors it has are on an I2C bus connected to an I2C bus adapter that we don't support.
1564<li>You don't have the latest version of lm_sensors.
1565        </ol>
1566
1567   <p>But in any case you should figure out what is on the board:
1568     <ol type=1 start=1>
1569<li>Look at your motherboard.
1570<li>Check the manufacturer's website.
1571<li>Check the <a href="http://mbm.livewiredev.com/">Motherboard Monitor</a> website.
1572        </ol>
1573
1574   <p>When you know what chips you have, check the
1575<a href="http://www2.lm-sensors.nu/~lm78/newdrivers.html">Newest Driver Status</a> web page to
1576see if support has been added for your chip in a later release or in CVS.
1577
1578<div class="node">
1579<p><hr>
1580<a name="Section-4_002e25"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e26">Section 4.26</a>,
1581Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e24">Section 4.24</a>,
1582Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1583<br>
1584</div>
1585
1586<h3 class="section">4.25 Sensors says <span class="samp">Error: Line xxx: zzzzzzz</span></h3>
1587
1588<p>These are errors from the libsensors library in
1589reading the <span class="file">/etc/sensors.conf</span> configuration file. Go to that line
1590number and fix it. If you have a parse error, perhaps you have
1591to put the feature name in double quotes.
1592
1593<div class="node">
1594<p><hr>
1595<a name="Section-4_002e26"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e27">Section 4.27</a>,
1596Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e25">Section 4.25</a>,
1597Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1598<br>
1599</div>
1600
1601<h3 class="section">4.26 Sensors only gives the name, adapter, and algorithm for my chip</h3>
1602
1603<p>If <span class="command">sensors</span> only says this, for example, and doesn't
1604provide any actual data at all:
1605
1606<pre class="example">     it87-isa-0290
1607     Adapter: ISA adapter
1608     Algorithm: ISA algorithm
1609</pre>
1610   <p>Your chip is not currently supported by <span class="command">sensors</span> and so all it
1611does is print out that information. Get the latest release
1612and be sure you are running the <span class="command">sensors</span> program it installed
1613and not some older <span class="command">sensors</span>.
1614
1615<div class="node">
1616<p><hr>
1617<a name="Section-4_002e27"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e28">Section 4.28</a>,
1618Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e26">Section 4.26</a>,
1619Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1620<br>
1621</div>
1622
1623<h3 class="section">4.27 Sensors says <span class="samp">ERROR: Can't get xxxxx data!</span></h3>
1624
1625     <ul>
1626<li>(Linux 2.6) Make sure you are using one of the
1627<a href="http://secure.netroedge.com/~lm78/kernel26.html">recommended kernel/lm_sensors combination</a>.
1628<li>You have a <span class="file">libsensors</span>/<span class="command">sensors</span> mismatch.
1629<span class="command">sensors</span> is unable to
1630get a data entry from <span class="file">libsensors</span>. You probably have an
1631old <span class="file">libsensors</span> in your <span class="file">/etc/ld.so.conf</span> path.
1632Make sure you did (as root) a <span class="command">make install</span> (Linux 2.4) or
1633<span class="command">make user_install</span> (Linux 2.6) followed by a <span class="command">ldconfig</span>.
1634Then check the output of <span class="command">ldconfig -v | grep libsensors</span> to
1635verify that there is only ONE <span class="file">libsensors</span> entry and that it matches
1636the <span class="file">libsensors</span> that was built in the <span class="file">lib/</span> directory in <span class="file">lm_sensors2</span>.
1637</ul>
1638
1639<div class="node">
1640<p><hr>
1641<a name="Section-4_002e28"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e29">Section 4.29</a>,
1642Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e27">Section 4.27</a>,
1643Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1644<br>
1645</div>
1646
1647<h3 class="section">4.28 Sensors doesn't find any sensors, just eeproms.</h3>
1648
1649<p>See <a href="#Section-4_002e24">Sensors-detect doesnt work at all</a>, if <span class="command">sensors-detect</span> failed to find any sensors.
1650
1651   <p>If <span class="command">sensors-detect</span> did find sensors, did you insert your modules? For chips on the ISA
1652bus, did you insert i2c-isa?
1653
1654   <p>See <a href="#Section-5_002e2">What to do if a module wont insert</a>, if the modules didn't insert,
1655also <a href="#Section-4_002e21">Sensors says No sensors found</a>.
1656
1657<div class="node">
1658<p><hr>
1659<a name="Section-4_002e29"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e30">Section 4.30</a>,
1660Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e28">Section 4.28</a>,
1661Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1662<br>
1663</div>
1664
1665<h3 class="section">4.29 Inserting modules hangs my board</h3>
1666
1667<p>There are several possible causes:
1668     <ol type=1 start=1>
1669<li>Bus driver problems. Insert the bus driver first, before you have inserted any chip drivers, to verify.
1670<li>Wrong chip driver. Verify that you have a chip supported by the chip driver, see <a href="#Section-3_002e2_002e1">What chips are on motherboard XYZ</a>.
1671<li>The chip driver is reinitializing the chip, which undoes critical initialization done by the BIOS.  Try the parameter <span class="command">init=0</span> for the w83781d driver; this is the only driver supporting this parameter.
1672<li>Some chips on the bus don't like to be probed at all.  After inserting the bus driver (but not the chip drivers), run <span class="command">i2cdetect</span> on the bus, then <span class="command">i2cdump</span> on each address responding to <span class="command">i2cdetect</span>. This may find the culprit.  Do not <span class="command">i2cdump address 0x69</span>, the clock chip.
1673<li>The chip driver is incorrectly finding a second chip on the bus and is accessing it. For example, with the Tyan 2688 with a w83781d at 0x29, use <span class="command">modprobe ignore_range=0,0x00,0x28,0,0x2a,0x7f</span> to prevent access to other addresses. (<span class="command">init=0</span> also req'd for the Tyan 2688).
1674        </ol>
1675
1676<div class="node">
1677<p><hr>
1678<a name="Section-4_002e30"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e31">Section 4.31</a>,
1679Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e29">Section 4.29</a>,
1680Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1681<br>
1682</div>
1683
1684<h3 class="section">4.30 Inserting modules slows down my board</h3>
1685
1686<p>Generally this is caused by an overtemperature alarm output from
1687the sensor chip. This triggers hardware on the board which
1688automatically slows down the CPU clock. Be sure that your
1689temperature limits are above the temperature reading. Put
1690the new limits in <span class="file">/etc/sensors.conf</span> and run <span class="command">sensors -s</span>.
1691
1692<div class="node">
1693<p><hr>
1694<a name="Section-4_002e31"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e32">Section 4.32</a>,
1695Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e30">Section 4.30</a>,
1696Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1697<br>
1698</div>
1699
1700<h3 class="section">4.31 Problems on particular motherboards</h3>
1701
1702<p>The following boards have unique problems and solutions.
1703
1704   <p><a name="Asus-P4B"></a>
1705
1706<h4 class="subsection">4.31.1 Asus P4B</h4>
1707
1708<p>See <span class="file">prog/hotplug/README.p4b</span> if your SMBus master is not found.
1709
1710   <p><a name="Tyan-2460-2462"></a>
1711
1712<h4 class="subsection">4.31.2 Tyan 2460, 2462</h4>
1713
1714<p>See support tickets 805, 765, 781, 812, 813, and 867 for information.
1715
1716   <p><a name="Tyan-2466"></a>
1717
1718<h4 class="subsection">4.31.3 Tyan 2466</h4>
1719
1720<p>See support tickets 941, 840, and 841 for information.
1721
1722   <p><a name="Tyan-2688"></a>
1723
1724<h4 class="subsection">4.31.4 Tyan 2688</h4>
1725
1726<p>For board hangs, see support ticket 721 for information.
1727Also <a href="#Section-4_002e29">Inserting modules hangs my board</a>.
1728
1729<div class="node">
1730<p><hr>
1731<a name="Section-4_002e32"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-4_002e33">Section 4.33</a>,
1732Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e31">Section 4.31</a>,
1733Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1734<br>
1735</div>
1736
1737<h3 class="section">4.32 Problems on particular systems</h3>
1738
1739<p>For IBM systems, see <span class="file">README.thinkpad</span>.
1740
1741<div class="node">
1742<p><hr>
1743<a name="Section-4_002e33"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-4_002e32">Section 4.32</a>,
1744Up:&nbsp;<a rel="up" accesskey="u" href="#Problems">Problems</a>
1745<br>
1746</div>
1747
1748<h3 class="section">4.33 Problems on 2.6 kernels</h3>
1749
1750<p>Not all drivers have been ported to 2.6. If your favorite driver is not
1751in 2.6, the reason is that nobody has ported it.
1752Please don't bother asking us why it is not in 2.6.
1753If you would like to port the driver, see the file
1754Documentation/i2c/porting-clients in the 2.6 kernel tree for help,
1755then send us the ported driver when you are done.
1756
1757<h4 class="subsection">4.33.1 i2c-viapro and via686a</h4>
1758
1759<p>Until kernel 2.6.11, there was a PCI resource conflict between
1760i2c-viapro (the SMBus driver for VIA bridges) and via686a (the integrated
1761sensors driver for VIA bridges). This caused the second loaded driver to
1762silently fail working. So do not load both i2c-viapro and via686a together
1763unless you have a recent kernel.
1764
1765<div class="node">
1766<p><hr>
1767<a name="Help"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Contribute">Contribute</a>,
1768Previous:&nbsp;<a rel="previous" accesskey="p" href="#Problems">Problems</a>,
1769Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
1770<br>
1771</div>
1772
1773<h2 class="chapter">5 How to Ask for Help</h2>
1774
1775<ul class="menu">
1776<li><a accesskey="1" href="#Section-5_002e1">Section 5.1</a>:   What to send us when asking for help
1777<li><a accesskey="2" href="#Section-5_002e2">Section 5.2</a>:   What to do if a module won't insert?
1778<li><a accesskey="3" href="#Section-5_002e3">Section 5.3</a>:   What to do if it inserts, but nothing happens?
1779<li><a accesskey="4" href="#Section-5_002e4">Section 5.4</a>:   What to do if I read only bogus information?
1780<li><a accesskey="5" href="#Section-5_002e5">Section 5.5</a>:   What to do if you have other problems?
1781<li><a accesskey="6" href="#Section-5_002e6">Section 5.6</a>:   What if it just works like a charm?
1782<li><a accesskey="7" href="#Section-5_002e7">Section 5.7</a>:   How do I update a ticket?
1783<li><a accesskey="8" href="#Section-5_002e8">Section 5.8</a>:   How do I follow up on a ticket?
1784</ul>
1785
1786<div class="node">
1787<p><hr>
1788<a name="Section-5_002e1"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-5_002e2">Section 5.2</a>,
1789Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1790<br>
1791</div>
1792
1793<h3 class="section">5.1 What to send us when asking for help</h3>
1794
1795<p>We are always willing to answer questions if things don't work out.
1796Please email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>, and not the individual authors,
1797unless you have something private to say.
1798
1799   <p>Instead of using email, you can also use the web-based support
1800area, at <a href="http://secure.netroedge.com/~lm78/support.html">http://secure.netroedge.com/~lm78/support.html</a>. You will be helped
1801just as fast, and others may profit from the answer too. You will be
1802emailed automatically when your question has been answered.
1803
1804   <p>Here's what you should send us:
1805
1806     <ul>
1807<li>The dmesg or syslog output if applicable
1808<li>The output of (as root) <span class="command">prog/detect/sensors-detect</span>
1809<li>The output of <span class="command">lsmod</span>
1810<li>If a PCI chip problem:
1811          <ul>
1812<li>The output of <span class="command">lspci -n</span>
1813</ul>
1814     <li>If an I2C sensor chip problem:
1815          <ul>
1816<li>The output of (as root) <span class="command">prog/detect/i2cdetect X</span>
1817where X = the bus number (run <span class="command">i2cdetect</span> with no arguments to list the busses)
1818(please send this only if it's not all <span class="samp">XX</span>)
1819<li>The output of (as root) <span class="command">prog/dump/i2cdump X 0xXX</span>
1820where XX = the address of each chip you see in the output of <span class="command">i2cdetect</span>. (run once for each chip)
1821(please send this only if it's not all <span class="samp">ff</span>)
1822</ul>
1823     <li>If an ISA sensor chip problem:
1824          <ul>
1825<li>The output of (as root) <span class="command">prog/dump/isadump 0x295 0x296</span> (only if it's not all <span class="samp">XX</span>)
1826</ul>
1827     <li>Part numbers of chips on your motherboard you think are the sensor chips (look at your motherboard)
1828<li>Motherboard type
1829<li>Sensors version
1830<li>Kernel version
1831</ul>
1832
1833<div class="node">
1834<p><hr>
1835<a name="Section-5_002e2"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-5_002e3">Section 5.3</a>,
1836Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-5_002e1">Section 5.1</a>,
1837Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1838<br>
1839</div>
1840
1841<h3 class="section">5.2 What to do if a module won't insert?</h3>
1842
1843<p>Did you use <span class="command">modprobe</span> instead of <span class="command">insmod</span>??? Don't use insmod.
1844
1845   <p>Were there unresolved symbols? Did you run <span class="command">depmod -a</span>? Run
1846<span class="command">depmod -a -e</span> to see where the symbol problem is.
1847
1848   <p>ALWAYS inspect the output of <span class="command">dmesg</span>. That's where the error
1849messages come out!!! Don't rely on the generic message from <span class="command">modprobe</span>.
1850If you still can't figure it out, send us the information
1851listed above.
1852
1853<div class="node">
1854<p><hr>
1855<a name="Section-5_002e3"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-5_002e4">Section 5.4</a>,
1856Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-5_002e2">Section 5.2</a>,
1857Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1858<br>
1859</div>
1860
1861<h3 class="section">5.3 What to do if it inserts, but nothing happens?</h3>
1862
1863<p>For an ISA sensor chip, did you also <span class="command">modprobe i2c-isa</span>? It must be inserted.
1864
1865   <p>For an I2C sensor chip, did you also <span class="command">modprobe i2c-xxx</span> where xxx is your
1866I2C bus adapter? It must be inserted.
1867
1868   <p>Always inspect the output of <span class="command">dmesg</span>. That's where the error
1869messages come out. If you still can't figure it out, send us the information
1870listed above.
1871
1872<div class="node">
1873<p><hr>
1874<a name="Section-5_002e4"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-5_002e5">Section 5.5</a>,
1875Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-5_002e3">Section 5.3</a>,
1876Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1877<br>
1878</div>
1879
1880<h3 class="section">5.4 What to do if I read only bogus information?</h3>
1881
1882<p>It may be that this was a mis-detection: the chip may not be
1883present. If you are convinced there is something wrong, verify that you
1884indeed have the devices on your motherboard that you think you do.
1885Look at the motherboard and make sure. If you are still stuck,
1886please send us the usual information (see <a href="#Help">Help</a>)
1887
1888<div class="node">
1889<p><hr>
1890<a name="Section-5_002e5"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-5_002e6">Section 5.6</a>,
1891Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-5_002e4">Section 5.4</a>,
1892Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1893<br>
1894</div>
1895
1896<h3 class="section">5.5 What to do if you have other problems?</h3>
1897
1898<p>Again, send the output listed above.
1899
1900<div class="node">
1901<p><hr>
1902<a name="Section-5_002e6"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-5_002e7">Section 5.7</a>,
1903Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-5_002e5">Section 5.5</a>,
1904Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1905<br>
1906</div>
1907
1908<h3 class="section">5.6 What if it just works like a charm?</h3>
1909
1910<p>Drop us a mail if you feel like it, mentioning the mainboard and
1911detected chip type. That way, we have some positive feedback, too!
1912
1913<div class="node">
1914<p><hr>
1915<a name="Section-5_002e7"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-5_002e8">Section 5.8</a>,
1916Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-5_002e6">Section 5.6</a>,
1917Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1918<br>
1919</div>
1920
1921<h3 class="section">5.7 How do I update a ticket?</h3>
1922
1923<p>You can't. Only developers can. Follow up by emailing us
1924at <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a> and reference your ticket number
1925in the subject. Please don't enter a new ticket with
1926follow-up information, email us instead. Thanks.
1927
1928<div class="node">
1929<p><hr>
1930<a name="Section-5_002e8"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-5_002e7">Section 5.7</a>,
1931Up:&nbsp;<a rel="up" accesskey="u" href="#Help">Help</a>
1932<br>
1933</div>
1934
1935<h3 class="section">5.8 How do I follow up on a ticket?</h3>
1936
1937<p>Follow up by emailing us at <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>
1938and reference your ticket number in the subject.
1939
1940<div class="node">
1941<p><hr>
1942<a name="Contribute"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Version-1-Specifics">Version 1 Specifics</a>,
1943Previous:&nbsp;<a rel="previous" accesskey="p" href="#Help">Help</a>,
1944Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
1945<br>
1946</div>
1947
1948<h2 class="chapter">6 How to Contribute</h2>
1949
1950<ul class="menu">
1951<li><a accesskey="1" href="#Section-6_002e1">Section 6.1</a>:   How to write a driver
1952<li><a accesskey="2" href="#Section-6_002e2">Section 6.2</a>:   How to get CVS access
1953<li><a accesskey="3" href="#Section-6_002e3">Section 6.3</a>:   How to donate hardware to the project
1954<li><a accesskey="4" href="#Section-6_002e4">Section 6.4</a>:   How to join the project mailing list
1955<li><a accesskey="5" href="#Section-6_002e5">Section 6.5</a>:   How to access mailing list archives
1956<li><a accesskey="6" href="#Section-6_002e6">Section 6.6</a>:   How to submit a patch
1957<li><a accesskey="7" href="#Section-6_002e7">Section 6.7</a>:   How to REALLY help
1958<li><a accesskey="8" href="#Section-6_002e8">Section 6.8</a>:   How to get release announcements
1959<li><a accesskey="9" href="#Section-6_002e9">Section 6.9</a>:   How to block spam on the project mailing list
1960</ul>
1961
1962<div class="node">
1963<p><hr>
1964<a name="Section-6_002e1"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e2">Section 6.2</a>,
1965Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
1966<br>
1967</div>
1968
1969<h3 class="section">6.1 How to write a driver</h3>
1970
1971<p>See <span class="file">doc/developers/new_drivers</span> in our package for instructions.
1972
1973<div class="node">
1974<p><hr>
1975<a name="Section-6_002e2"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e3">Section 6.3</a>,
1976Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e1">Section 6.1</a>,
1977Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
1978<br>
1979</div>
1980
1981<h3 class="section">6.2 How to get CVS access</h3>
1982
1983<p>For anonymous CVS read access, see the instructions on our download page.
1984Sorry, we don't have automatically generated CVS tarballs.
1985
1986   <p>For write access, run the script <span class="command">doc/developers/genpasswd.pl</span> in
1987our package and follow the instructions. Let us know what part
1988of the package you would like to work on.
1989
1990<div class="node">
1991<p><hr>
1992<a name="Section-6_002e3"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e4">Section 6.4</a>,
1993Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e2">Section 6.2</a>,
1994Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
1995<br>
1996</div>
1997
1998<h3 class="section">6.3 How to donate hardware to the project</h3>
1999
2000<p>Send us email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>.
2001
2002<div class="node">
2003<p><hr>
2004<a name="Section-6_002e4"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e5">Section 6.5</a>,
2005Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e3">Section 6.3</a>,
2006Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
2007<br>
2008</div>
2009
2010<h3 class="section">6.4 How to join the project mailing list</h3>
2011
2012<p>Send us email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>. Sorry,
2013there is no automated subscribe/unsubscribe service yet
2014(but we're seriously thinking of switching to majordomo).
2015Therefore there may be some delay before your request is processed.
2016Please note that you do NOT need to be subscribed to the list
2017in order to post. If you simply need help as a user, post your
2018detailed problem and questions directly. Don't worry, you'll be
2019CC'd on all replies.
2020
2021<div class="node">
2022<p><hr>
2023<a name="Section-6_002e5"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e6">Section 6.6</a>,
2024Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e4">Section 6.4</a>,
2025Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
2026<br>
2027</div>
2028
2029<h3 class="section">6.5 How to access mailing list archives</h3>
2030
2031<p>The primary mailing list archive is at:
2032<a href="http://lists.lm-sensors.org/pipermail/lm-sensors/">http://lists.lm-sensors.org/pipermail/lm-sensors/</a>.
2033It contains messages since October 28, 2001.
2034
2035   <p>There is another mailing list archive at:
2036<a href="http://news.gmane.org/gmane.linux.drivers.sensors">http://news.gmane.org/gmane.linux.drivers.sensors</a>.
2037It contains messages since December 31, 2004.
2038This archive may also be accessed via a news reader:
2039<a href="nntp://news.gmane.org/gmane.linux.drivers.sensors">nntp://news.gmane.org/gmane.linux.drivers.sensors</a>
2040and RSS:
2041<a href="http://rss.gmane.org/gmane.linux.drivers.sensors">http://rss.gmane.org/gmane.linux.drivers.sensors</a>.
2042
2043   <p>And last there is a legacy archive at:
2044<a href="http://archives.andrew.net.au/lm-sensors">http://archives.andrew.net.au/lm-sensors</a>.
2045It contains messages from October 28, 2001 through May 16, 2005.
2046
2047<div class="node">
2048<p><hr>
2049<a name="Section-6_002e6"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e7">Section 6.7</a>,
2050Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e5">Section 6.5</a>,
2051Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
2052<br>
2053</div>
2054
2055<h3 class="section">6.6 How to submit a patch</h3>
2056
2057<p>Check out the latest from CVS, then copy the directory to another
2058directory, and make your changes. Generate the diff with
2059<span class="command">diff -u2 -r DIR1 DIR2</span>. Or you can generate the diff in CVS with
2060<span class="command">cvs diff -u2</span>. Send us the patch in an email and tell us what it does.
2061
2062<div class="node">
2063<p><hr>
2064<a name="Section-6_002e7"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e8">Section 6.8</a>,
2065Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e6">Section 6.6</a>,
2066Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
2067<br>
2068</div>
2069
2070<h3 class="section">6.7 How to REALLY help</h3>
2071
2072<p>Believe it or not, what we really need help with are:
2073     <ul>
2074<li>Answering email
2075<li>Answering support tickets
2076<li>Submitting patches to Linus, etc.
2077<li>Creating a sensors.conf database
2078<li>Creating RPM's
2079</ul>
2080
2081   <p>Send us email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a> if you can help.
2082No experience necessary :)
2083
2084<div class="node">
2085<p><hr>
2086<a name="Section-6_002e8"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-6_002e9">Section 6.9</a>,
2087Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e7">Section 6.7</a>,
2088Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
2089<br>
2090</div>
2091
2092<h3 class="section">6.8 How to get release announcements</h3>
2093
2094<p>We don't have a separate release announcement mailing list;
2095however, we put all our releases on freshmeat: <a href="http://freshmeat.net">http://freshmeat.net</a>
2096and you can register on our freshmeat project page  <a href="http://freshmeat.net/projects/lm_sensors">http://freshmeat.net/projects/lm_sensors</a>
2097to 'subscribe to new releases' and then freshmeat
2098will email you announcement.
2099
2100<div class="node">
2101<p><hr>
2102<a name="Section-6_002e9"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-6_002e8">Section 6.8</a>,
2103Up:&nbsp;<a rel="up" accesskey="u" href="#Contribute">Contribute</a>
2104<br>
2105</div>
2106
2107<h3 class="section">6.9 How to block spam on the project mailing list</h3>
2108
2109<p>Sorry, we know the spam is a hassle.  It would be nice to have a
2110moderator who can screen everything, but that takes too much time and
2111delays emails.  Right now there is a procmail script which tags likely
2112spam and puts in a X-SBClass: header.  If it is followed by 'Spam', then
2113it is almost certainly spam, if it is followed by 'Blocked', then it
2114scores high as being potential spam.  You should be able to set some
2115rules in your mail client to throw those emails into a seperate folder.
2116It's not bullet proof (some legit mails get tagged wrong, and vice
2117versa), but it seems to be about 95% accurate in our experience.
2118
2119<div class="node">
2120<p><hr>
2121<a name="Version-1-Specifics"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Document-Revisions">Document Revisions</a>,
2122Previous:&nbsp;<a rel="previous" accesskey="p" href="#Contribute">Contribute</a>,
2123Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
2124<br>
2125</div>
2126
2127<h2 class="chapter">7 Version 1 Specific Questions</h2>
2128
2129<ul class="menu">
2130<li><a accesskey="1" href="#Section-7_002e1">Section 7.1</a>:   My mainboard has an SMBus, your code can't find it.  Why?
2131<li><a accesskey="2" href="#Section-7_002e2">Section 7.2</a>:   The modules won't load, saying 'SMBus not detected'.
2132<li><a accesskey="3" href="#Section-7_002e3">Section 7.3</a>:   I get a "No sensor data yet (try again in a few moments)" msg.
2133<li><a accesskey="4" href="#Section-7_002e4">Section 7.4</a>:   On my Dell, a LM80 is detected, but all readings are 0!
2134</ul>
2135
2136<p>Note: Version 1 is very very old and is not recommended.
2137
2138<div class="node">
2139<p><hr>
2140<a name="Section-7_002e1"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-7_002e2">Section 7.2</a>,
2141Up:&nbsp;<a rel="up" accesskey="u" href="#Version-1-Specifics">Version 1 Specifics</a>
2142<br>
2143</div>
2144
2145<h3 class="section">7.1 My manufacturer swears that my mainboard has an SMBus, but your code reports that it can't find it.  What's wrong?</h3>
2146
2147<p>Currently, our code only assumes that an SMBus exists if it originates
2148from the Intel PIIX4 (82371AB).  If your computer doesn't have one, or if your
2149SMBus originates from a different SMBus 'host', then you are out of luck. :'(
2150Our experience is, though, that most machines have a PIIX4, and that it is
2151where the SMBus is hosted.
2152
2153   <p>Regarding the VIA chip set(s):
2154
2155   <p>Right now, the SMBus code depends on the Intel PIIX4 chip to handle
2156SMBus transactions.  The VIA chip set is NOT supported at this time because
2157it forces much of the SMBus protocol to be implemented by software.
2158
2159   <p>To implement the SMBus correctly with the VIA chip, it needs to be
2160written at a low level to be quick.  A more attractive alternative is to
2161use the Bios SMBus interface (not always available nor standard).
2162
2163   <p>Version 2 supports the VIA chipset, and will support other chipsets.
2164Version 1 never will.
2165
2166<div class="node">
2167<p><hr>
2168<a name="Section-7_002e2"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-7_002e3">Section 7.3</a>,
2169Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-7_002e1">Section 7.1</a>,
2170Up:&nbsp;<a rel="up" accesskey="u" href="#Version-1-Specifics">Version 1 Specifics</a>
2171<br>
2172</div>
2173
2174<h3 class="section">7.2 The modules won't load, saying 'SMBus not detected'.</h3>
2175
2176<p>This should no longer be an issue in 1.4.10 and later; it will
2177continue loading, but it won't support SMBus-connected devices, of course.
2178
2179<div class="node">
2180<p><hr>
2181<a name="Section-7_002e3"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Section-7_002e4">Section 7.4</a>,
2182Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-7_002e2">Section 7.2</a>,
2183Up:&nbsp;<a rel="up" accesskey="u" href="#Version-1-Specifics">Version 1 Specifics</a>
2184<br>
2185</div>
2186
2187<h3 class="section">7.3 I try to read <span class="file">/proc/sensors</span>, and I get a "No sensor data yet (try again in a few moments)" message. Why?</h3>
2188
2189<p>It takes about 1.5 seconds for the LM78 to update all its sensor
2190values.  If we would try to read it before it finished that, you would get
2191old garbage instead. So you have to wait 1.5 seconds after the module is
2192inserted before you can access <span class="file">/proc/sensors</span>.
2193
2194   <p>Module versions 1.3.7 and later let the process sleep if it tries
2195to access sensor data right after insertion time, and do not display this
2196message anymore.
2197
2198<div class="node">
2199<p><hr>
2200<a name="Section-7_002e4"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Section-7_002e3">Section 7.3</a>,
2201Up:&nbsp;<a rel="up" accesskey="u" href="#Version-1-Specifics">Version 1 Specifics</a>
2202<br>
2203</div>
2204
2205<h3 class="section">7.4 On my Dell, a LM80 is detected, but all readings are 0!</h3>
2206
2207<p>This is a bug we have only observed on Dell computers. There is
2208probably a problem with the way the SMBus is accessed; but it is not yet
2209clear whether the problem is in our code or with the Dells.
2210
2211   <p>There are very probably no sensor chips at all on your computer;
2212but until somebody contacts Dell about this and tells us the results, we
2213can not be sure.
2214
2215<div class="node">
2216<p><hr>
2217<a name="Document-Revisions"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Version-1-Specifics">Version 1 Specifics</a>,
2218Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
2219<br>
2220</div>
2221
2222<h2 class="appendix">Appendix A Revision History of This Document</h2>
2223
2224     <ul>
2225<li>Rev 2.10 (MDS) Various updates, 20040103
2226<li>Rev 2.9 (CP) Converted to Gnu texinfo format, 20020910
2227<li>Rev 2.8 (MDS) Minor updates 20020710, released with lm_sensors 2.6.4
2228<li>Rev 2.7 (MDS) Minor updates 20020425
2229<li>Rev 2.6 (MDS) Minor updates 20020115, released with lm_sensors 2.6.3
2230<li>Rev 2.5 (MDS) Minor updates 20011111, released with lm_sensors 2.6.2
2231<li>Rev 2.4 (MDS) Minor updates 20010722
2232<li>Rev 2.3 (MDS) General update, 20010224, released with lm_sensors 2.6.0.
2233<li>Rev 2.2 (Frodo) Corrections for lm_sensors 2.4, 19990920
2234<li>Rev 2.1 (Frodo) Corrections for lm_sensors 2.2, 19990112
2235<li>Rev 2.0 (Frodo) Major revision for lm_sensors 2.1, 19981229
2236<li>Rev 1.10 (Frodo) Modified 3.8, updated some other things, 19980924
2237<li>Rev 1.9 (Frodo) Added 3.15, 19980906
2238<li>Rev 1.8 (Frodo) Added 3.14, 19980905
2239<li>Rev 1.7 (Phil) Added 3.13 and some other minor changes, 19980901
2240<li>Rev 1.6 (Frodo) Added 4, 4.1, 4.2, 4.3, 4.4, 4.5, 19980901
2241<li>Rev 1.5 (Frodo) Added 2.3, 2.4, 3.9, 3.10, 3.11, 19980826
2242<li>Rev 1.4 (Frodo) Added some more Winbond information, and 3.5-3.8, 19980817
2243<li>Rev 1.3 Added info on the Winbond chip, 19980816
2244<li>Rev 1.2 Adapation by Frodo Looijaard, 19980810
2245<li>Rev 1.1 Modifications by Philip Edelbrock, 19980809
2246<li>Rev 1.0 Written by Philip Edelbrock, 19980803
2247</ul>
2248
2249</body></html>
2250
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