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3	<title>Sensors FAQ for lm_sensors version 2.9</title>
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10	<h1>Sensors FAQ for lm_sensors version 2.9</h1>
11	Copyright (c) 1998 - 2002<br>
12	<a href="mailto:frodol@dds.nl">Frodo Looijaard</a>,<br>
13	<a href="mailto:phil@netroedge.com">Philip Edelbrock</a>,<br>
14	and<br>
15	<a href="mailto:mdsxyz123@yahoo.com">Mark Studebaker</a><br>
16
17
18	<h2>Short Contents</h2>
19	<ul>
20	<li><a href="#toc_Top">lm_sensors</a>
21	<li><a href="#toc_Overview">1 PC and Sensor Overview</a>
22	<li><a href="#toc_Basics">2 Sensor and Bus Basics</a>
23	<li><a href="#toc_Installation">3 Installation and Management</a>
24	<li><a href="#toc_Problems">4 Problems</a>
25	<li><a href="#toc_Help">5 How to Ask for Help</a>
26	<li><a href="#toc_Contribute">6 How to Contribute</a>
27	<li><a href="#toc_Version%201%20Specifics">7 Version 1 Specific Questions</a>
28	<li><a href="#toc_Document%20Revisions">Appendix A Revision History of This Document</a>
29	</ul>
30
31
32	<h2>Table of Contents</h2>
33	<ul>
34	<li><a name="toc_Top"></a>
35	<a href="#Top">lm_sensors</a>
36	<li><a name="toc_Overview"></a>
37	<a href="#Overview">1 PC and Sensor Overview</a>
38	<ul>
39	<li><a href="#Section%201.1">1.1 What sensors are available on my PC?</a>
40	<li><a href="#Section%201.2">1.2 What can a sensor chip like the "LM78" do?</a>
41	<li><a href="#Section%201.3">1.3 Where do I find out more about any of these chips?</a>
42	</ul>
43	<li><a name="toc_Basics"></a>
44	<a href="#Basics">2 Sensor and Bus Basics</a>
45	<ul>
46	<li><a href="#Section%202.1">2.1 How are these sensors read?</a>
47	<li><a href="#Section%202.2">2.2 What is the SMBus? And the I2C bus?</a>
48	<li><a href="#Section%202.3">2.3 I don't have an ISA bus!</a>
49	<li><a href="#Section%202.4">2.4 What sensors do processors have?</a>
50	<li><a href="#Section%202.5">2.5 How often are the sensor values updated?</a>
51	<li><a href="#Section%202.6">2.6 How are alarms triggered?</a>
52	</ul>
53	<li><a name="toc_Installation"></a>
54	<a href="#Installation">3 Installation and Management</a>
55	<ul>
56	<li><a href="#Section%203.1">3.1 Why so many modules, and how do I cope with them?</a>
57	<li><a href="#Section%203.2">3.2 How do I know which chips I own?</a>
58	<ul>
59	<li><a href="#Section%203.2">3.2.1 What chips are on motherboard XYZ?</a>
60	<li><a href="#Section%203.2">3.2.2 Do you support motherboard XYZ?</a>
61	<li><a href="#Section%203.2">3.2.3 Do you support chip XYZ?</a>
62	<li><a href="#Section%203.2">3.2.4 Anybody working on a driver for chip XYZ?</a>
63	</ul>
64	<li><a href="#Section%203.3">3.3 Which modules should I insert?</a>
65	<li><a href="#Section%203.4">3.4 Do I need the configuration file <code>/etc/sensors.conf</code>?</a>
66	<ul>
67	<li><a href="#Section%203.4">3.4.1 The labels for the voltage and temperature readings in <code>sensors</code> are incorrect!</a>
68	<li><a href="#Section%203.4">3.4.2 The min and max for the readings in <code>sensors</code> are incorrect!</a>
69	<li><a href="#Section%203.4">3.4.3 The min and max settings in <code>/etc/sensors.conf</code> didn't take effect!</a>
70	<li><a href="#Section%203.4">3.4.4 One sensor isn't hooked up on my board!</a>
71	<li><a href="#Section%203.4">3.4.5 I need help with <code>sensors.conf</code>!</a>
72	<li><a href="#Section%203.4">3.4.6 Do you have a database of <code>sensors.conf</code> entries for specific boards?</a>
73	</ul>
74	<li><a href="#Section%203.5">3.5 What about the <code>No such file or directory</code> warnings when I compile?</a>
75	<li><a href="#Section%203.6">3.6 I get all kinds of weird compilation errors?</a>
76	<ul>
77	<li><a href="#Section%203.6">3.6.1 <code>No rule to make target xxxx needed by xxxx</code> - how to fix?</a>
78	</ul>
79	<li><a href="#Section%203.7">3.7 It still does not compile or patch!</a>
80	<li><a href="#Section%203.8">3.8 <code>make install</code> fails on Mandrake kernels</a>
81	<li><a href="#Section%203.9">3.9 I get unresolved symbols when I <code>modprobe</code> modules (Red Hat especially)</a>
82	<li><a href="#Section%203.10">3.10 I2C_DRIVERID_ADM1024 undefined (Red Hat especially)</a>
83	</ul>
84	<li><a name="toc_Problems"></a>
85	<a href="#Problems">4 Problems</a>
86	<ul>
87	<li><a href="#Section%204.1">4.1 My fans report exactly half/double their values compared to the BIOS?</a>
88	<ul>
89	<li><a href="#Section%204.1">4.1.1 Fans sometimes/always read 0!!</a>
90	<li><a href="#Section%204.1">4.1.2 I doubled the fan divisor and the fan still reads 7000!</a>
91	</ul>
92	<li><a href="#Section%204.2">4.2 Why do my two LM75's report "-48 degrees"?</a>
93	<li><a href="#Section%204.3">4.3 Why do I have two Vcore readings, I have only one processor!</a>
94	<li><a href="#Section%204.4">4.4 How do those ALARMS work? The current value is within range but there is still an ALARM warning!</a>
95	<li><a href="#Section%204.5">4.5 My voltage readings seem to drift a bit. Is something wrong?</a>
96	<li><a href="#Section%204.6">4.6 Some measurements are way out of range. What happened?</a>
97	<li><a href="#Section%204.7">4.7 What are VID lines? Why is the VID reading wrong?</a>
98	<li><a href="#Section%204.8">4.8 I read sensor values several times a second, but they are only updated only each second or so. Why?</a>
99	<li><a href="#Section%204.9">4.9 It sometimes seems to take almost a second before I see the sensor reading results. Why?</a>
100	<li><a href="#Section%204.10">4.10 Can I be alerted when an ALARM occurs?</a>
101	<li><a href="#Section%204.11">4.11 SMBus transactions on my PIIX4 simply don't work (timeouts happen). Why?</a>
102	<li><a href="#Section%204.12">4.12 My BIOS reports a much higher CPU temperature than your modules!</a>
103	<li><a href="#Section%204.13">4.13 I try to read the raw <code>/proc</code> files, but the values are strange?!?</a>
104	<li><a href="#Section%204.14">4.14 How do I set new limits?</a>
105	<ul>
106	<li><a href="#Section%204.14">4.14.1 I set new limits and it didn't work?</a>
107	</ul>
108	<li><a href="#Section%204.15">4.15 Some sensors are doubly detected?</a>
109	<li><a href="#Section%204.16">4.16 I ran sensors-detect, but now I get very strange readings?!?</a>
110	<li><a href="#Section%204.17">4.17 Bad readings from particular chips</a>
111	<ul>
112	<li><a href="#Section%204.17">4.17.1 Bad readings from the AS99127F!</a>
113	<li><a href="#Section%204.17">4.17.2 Bad readings from the VIA 686A!</a>
114	<li><a href="#Section%204.17">4.17.3 Bad readings from the MTP008!</a>
115	<li><a href="#Section%204.17">4.17.4 Bad temperature readings from the SIS5595!</a>
116	<li><a href="#Section%204.17">4.17.5 Bad readings from a w8378[12]d!</a>
117	<li><a href="#Section%204.17">4.17.6 Bus hangs on Ali 1543 on Asus P5A boards!</a>
118	<li><a href="#Section%204.17">4.17.7 Bad readings from LM75!</a>
119	<li><a href="#Section%204.17">4.17.8 Bad readings from LM78!</a>
120	<li><a href="#Section%204.17">4.17.9 Bad readings from LM80!</a>
121	<li><a href="#Section%204.17">4.17.10 Bad readings from it87!</a>
122	</ul>
123	<li><a href="#Section%204.18">4.18 How do I configure two chips (LM87) differently?</a>
124	<li><a href="#Section%204.19">4.19 Dmesg says <code>Upgrade BIOS</code>! I don't want to!</a>
125	<ul>
126	<li><a href="#Section%204.19">4.19.1 Dmesg says <code>use force_addr=0xaddr</code>! What address do I use?</a>
127	</ul>
128	<li><a href="#Section%204.20">4.20 Sensors says <code>Can't access <code>/proc</code> file</code></a>
129	<li><a href="#Section%204.21">4.21 Sensors says <code>No sensors found!</code></a>
130	<li><a href="#Section%204.22">4.22 Sensors output is not correct!</a>
131	<li><a href="#Section%204.23">4.23 What is at I2C address XXX?</a>
132	<ul>
133	<li><a href="#Section%204.23">4.23.1 What is at I2C address 0x69?</a>
134	<li><a href="#Section%204.23">4.23.2 What is at I2C addresses 0x50 - 0x57?</a>
135	<li><a href="#Section%204.23">4.23.3 What is at I2C addresses 0x30 - 0x37?</a>
136	</ul>
137	<li><a href="#Section%204.24">4.24 Sensors-detect doesn't work at all</a>
138	<ul>
139	<li><a href="#Section%204.24">4.24.1 Sensors-detect says "Couldn't open /proc/bus/i2c?!?"</a>
140	<li><a href="#Section%204.24">4.24.2 Sensors-detect says "Can't open /dev/i2c[-/]0"</a>
141	<li><a href="#Section%204.24">4.24.3 Sensors-detect doesn't find any sensors!</a>
142	</ul>
143	<li><a href="#Section%204.25">4.25 Sensors says <code>Error: Line xxx: zzzzzzz</code></a>
144	<li><a href="#Section%204.26">4.26 Sensors only gives the name, adapter, and algorithm for my chip</a>
145	<li><a href="#Section%204.27">4.27 Sensors says <code>ERROR: Can't get xxxxx data!</code></a>
146	<li><a href="#Section%204.28">4.28 Sensors doesn't find any sensors, just eeproms.</a>
147	<li><a href="#Section%204.29">4.29 Inserting modules hangs my board</a>
148	<li><a href="#Section%204.30">4.30 Inserting modules slows down my board</a>
149	<li><a href="#Section%204.31">4.31 Problems on particular motherboards</a>
150	<ul>
151	<li><a href="#Section%204.31">4.31.1 Asus P4B</a>
152	<li><a href="#Section%204.31">4.31.2 Tyan 2460, 2462</a>
153	<li><a href="#Section%204.31">4.31.3 Tyan 2466</a>
154	<li><a href="#Section%204.31">4.31.4 Tyan 2688</a>
155	</ul>
156	<li><a href="#Section%204.32">4.32 Problems on particular systems</a>
157	</ul>
158	<li><a name="toc_Help"></a>
159	<a href="#Help">5 How to Ask for Help</a>
160	<ul>
161	<li><a href="#Section%205.1">5.1 What to send us when asking for help</a>
162	<li><a href="#Section%205.2">5.2 What to do if a module won't insert?</a>
163	<li><a href="#Section%205.3">5.3 What to do if it inserts, but nothing happens?</a>
164	<li><a href="#Section%205.4">5.4 What to do if I read only bogus information?</a>
165	<li><a href="#Section%205.5">5.5 What to do if you have other problems?</a>
166	<li><a href="#Section%205.6">5.6 What if it just works like a charm?</a>
167	<li><a href="#Section%205.7">5.7 How do I update a ticket?</a>
168	<li><a href="#Section%205.8">5.8 How do I follow up on a ticket?</a>
169	</ul>
170	<li><a name="toc_Contribute"></a>
171	<a href="#Contribute">6 How to Contribute</a>
172	<ul>
173	<li><a href="#Section%206.1">6.1 How to write a driver</a>
174	<li><a href="#Section%206.2">6.2 How to get CVS access</a>
175	<li><a href="#Section%206.3">6.3 How to donate hardware to the project</a>
176	<li><a href="#Section%206.4">6.4 How to join the project mailing list</a>
177	<li><a href="#Section%206.5">6.5 How to access mailing list archives</a>
178	<li><a href="#Section%206.6">6.6 How to submit a patch</a>
179	<li><a href="#Section%206.7">6.7 How to REALLY help</a>
180	<li><a href="#Section%206.8">6.8 How to get release announcements</a>
181	<li><a href="#Section%206.9">6.9 How to block spam on the project mailing list</a>
182	</ul>
183	<li><a name="toc_Version%201%20Specifics"></a>
184	<a href="#Version%201%20Specifics">7 Version 1 Specific Questions</a>
185	<ul>
186	<li><a href="#Section%207.1">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>
187	<li><a href="#Section%207.2">7.2 The modules won't load, saying 'SMBus not detected'.</a>
188	<li><a href="#Section%207.3">7.3 I try to read <code>/proc/sensors</code>, and I get a "No sensor data yet (try again in a few moments)" message. Why?</a>
189	<li><a href="#Section%207.4">7.4 On my Dell, a LM80 is detected, but all readings are 0!</a>
190	</ul>
191	<li><a name="toc_Document%20Revisions"></a>
192	<a href="#Document%20Revisions">Appendix A Revision History of This Document</a>
193	</ul>
194
195	<p><hr>
196	Node:<a name="Top">Top</a>,
197	Next:<a rel=next accesskey=n href="#Overview">Overview</a>,
198	Up:<a rel=up accesskey=u href="#dir">(dir)</a>
199	<br>
200
201	<h2>lm_sensors</h2>
202
203	<p>The lm_sensors package includes a collection of modules for general SMBus
204	access and hardware monitoring. NOTE: this requires special support which
205	is not in standard 2.2-vintage kernels.
206
207	<ul>
208	<li><a accesskey=1 href="#Overview">Overview</a>: PC and Sensor Overview
209	<li><a accesskey=2 href="#Basics">Basics</a>: Sensor and Bus Basics
210	<li><a accesskey=3 href="#Installation">Installation</a>: Installation and Management
211	<li><a accesskey=4 href="#Problems">Problems</a>: Problems
212	<li><a accesskey=5 href="#Help">Help</a>: How to Ask for Help
213	<li><a accesskey=6 href="#Contribute">Contribute</a>: How to Contribute
214	<li><a accesskey=7 href="#Version%201%20Specifics">Version 1 Specifics</a>: Version 1 Specific Questions
215	<li><a accesskey=8 href="#Document%20Revisions">Document Revisions</a>: Revision History of This Document
216	</ul>
217
218	<p><hr>
219	Node:<a name="Overview">Overview</a>,
220	Next:<a rel=next accesskey=n href="#Basics">Basics</a>,
221	Previous:<a rel=previous accesskey=p href="#Top">Top</a>,
222	Up:<a rel=up accesskey=u href="#Top">Top</a>
223	<br>
224
225	<h2>1 PC and Sensor Overview</h2>
226
227	<ul>
228	<li><a accesskey=1 href="#Section%201.1">Section 1.1</a>: What sensors are available on my PC?
229	<li><a accesskey=2 href="#Section%201.2">Section 1.2</a>: What can a sensor chip like the "LM78" do?
230	<li><a accesskey=3 href="#Section%201.3">Section 1.3</a>: Where do I find out more about any of these chips?
231	</ul>
232
233	<p><hr>
234	Node:<a name="Section%201.1">Section 1.1</a>,
235	Next:<a rel=next accesskey=n href="#Section%201.2">Section 1.2</a>,
236	Up:<a rel=up accesskey=u href="#Overview">Overview</a>
237	<br>
238
239	<h3>1.1 What sensors are available on my PC?</h3>
240
241	<p>Most PC's built since late 1997 now come with a
242	hardware health monitoring chip. This chip may be accessed via the
243	ISA bus or the SMBus, depending on the motherboard.
244
245	<p>Some motherboard chipsets, notably the Via 686 and the SiS 5595,
246	contain hardware monitor functions.
247
248	<p>This FAQ frequently refers to the "LM78". This chip has been
249	obsoleted by National Semiconductor. Most motherboards today contain
250	a chip with similar functions.
251
252	<p><hr>
253	Node:<a name="Section%201.2">Section 1.2</a>,
254	Next:<a rel=next accesskey=n href="#Section%201.3">Section 1.3</a>,
255	Previous:<a rel=previous accesskey=p href="#Section%201.1">Section 1.1</a>,
256	Up:<a rel=up accesskey=u href="#Overview">Overview</a>
257	<br>
258
259	<h3>1.2 What can a sensor chip like the "LM78" do?</h3>
260
261	<p>The LM78 is a chip made by National Semiconductor which can monitor 7
262	voltages (5 positive, 2 negative) from 0 to 4.08V. The inputs are usually in
263	series with voltage dividers which lower the +/- 12V and +/- 5V supplies to
264	measurable range. Therefore, the readings for such inputs need to be
265	re-scaled appropriately by software.
266
267	<p>The LM78 also has 3 fan speed monitoring inputs, an internal
268	temperature sensor, a chassis intrusion sensor, and a couple maskable interrupt
269	inputs. The LM78 can also relay the processor's (P6 or Pent II) VID lines
270	which are hardwired and used to indicate to the power regulator (usually on
271	the mainboard close to the processor socket/slot) what voltage to supply to
272	the processor.
273
274	<p>The LM78 can be interfaced to a system via the ISA bus and/or the
275	SMBus.
276
277	<p>Most other sensor chips have comparable functionality. Each supported
278	chip is documented in the <code>doc/chips</code> directory.
279
280	<p><hr>
281	Node:<a name="Section%201.3">Section 1.3</a>,
282	Previous:<a rel=previous accesskey=p href="#Section%201.2">Section 1.2</a>,
283	Up:<a rel=up accesskey=u href="#Overview">Overview</a>
284	<br>
285
286	<h3>1.3 Where do I find out more about any of these chips?</h3>
287
288	<p>Most semiconductor companies have comprehensive documentation,
289	including complete datasheets, on their websites. Analog Devices,
290	Dallas Semiconductor, Maxim, and National Semiconductor have the widest selection
291	of sensor chips. Their websites are:
292
293	<ul>
294	<li><a href="http://www.analog.com">http://www.analog.com</a>
295	<li><a href="http://www.dalsemi.com">http://www.dalsemi.com</a>
296	<li><a href="http://www.maxim-ic.com">http://www.maxim-ic.com</a>
297	<li><a href="http://www.national.com">http://www.national.com</a>
298	</ul>
299
300	<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>
301	for links to other companies' websites.
302
303	<p><hr>
304	Node:<a name="Basics">Basics</a>,
305	Next:<a rel=next accesskey=n href="#Installation">Installation</a>,
306	Previous:<a rel=previous accesskey=p href="#Overview">Overview</a>,
307	Up:<a rel=up accesskey=u href="#Top">Top</a>
308	<br>
309
310	<h2>2 Sensor and Bus Basics</h2>
311
312	<ul>
313	<li><a accesskey=1 href="#Section%202.1">Section 2.1</a>: What sensors are available on my PC?
314	<li><a accesskey=2 href="#Section%202.2">Section 2.2</a>: What can a sensor chip like the "LM78" do?
315	<li><a accesskey=3 href="#Section%202.3">Section 2.3</a>: Where do I find out more about any of these chips?
316	<li><a accesskey=4 href="#Section%202.4">Section 2.4</a>: What sensors are available on my PC?
317	<li><a accesskey=5 href="#Section%202.5">Section 2.5</a>: What can a sensor chip like the "LM78" do?
318	<li><a accesskey=6 href="#Section%202.6">Section 2.6</a>: Where do I find out more about any of these chips?
319	</ul>
320
321	<p><hr>
322	Node:<a name="Section%202.1">Section 2.1</a>,
323	Next:<a rel=next accesskey=n href="#Section%202.2">Section 2.2</a>,
324	Up:<a rel=up accesskey=u href="#Basics">Basics</a>
325	<br>
326
327	<h3>2.1 How are these sensors read?</h3>
328
329	<p>Sensor chips reside on either the ISA bus, the SMBus, or both.
330	See the file <code>doc/chips/SUMMARY</code> in our package for a list.
331
332	<p>To communicate with chips on the ISA bus, the software uses
333	simple I/O reads and writes.
334
335	<p>To communicate with chips on the SMBus, the software must
336	use an SMBus interface device, explained below.
337
338	<p><hr>
339	Node:<a name="Section%202.2">Section 2.2</a>,
340	Next:<a rel=next accesskey=n href="#Section%202.3">Section 2.3</a>,
341	Previous:<a rel=previous accesskey=p href="#Section%202.1">Section 2.1</a>,
342	Up:<a rel=up accesskey=u href="#Basics">Basics</a>
343	<br>
344
345	<h3>2.2 What is the SMBus? And the I2C bus?</h3>
346
347	<p>The SMBus is the "System Management Bus". More specifically, it is a
348	2-wire, low-speed serial communication bus used for basic health monitoring
349	and hardware management. It is a specific implementation of the more
350	general I2C (pronunciation: I-squared-C) bus. In fact, both I2C devices
351	and SMBus devices may be connected to the same (I2C) bus.
352
353	<p>The SMBus (or I2C bus) starts at the host controller, used for
354	starting transactions on the SMBus. From the host interface, the
355	devices communicated with are the <dfn>slave</dfn> devices. Each slave device has a
356	unique 7-bit address which the host uses to refer to that device.
357
358	<p>For each supported SMBus host, there is a separate kernel module
359	which implements the communication protocol with the host. Some SMBus hosts
360	really operate on the SMBus level; these hosts can not cope with pure I2C
361	devices. Other hosts are in fact I2C hosts: in this case, we implement
362	the SMBus protocol in terms of I2C operations. But these hosts can also
363	talk to pure I2C devices.
364
365	<p><hr>
366	Node:<a name="Section%202.3">Section 2.3</a>,
367	Next:<a rel=next accesskey=n href="#Section%202.4">Section 2.4</a>,
368	Previous:<a rel=previous accesskey=p href="#Section%202.2">Section 2.2</a>,
369	Up:<a rel=up accesskey=u href="#Basics">Basics</a>
370	<br>
371
372	<h3>2.3 I don't have an ISA bus!</h3>
373
374	<p>We promise, you do, even if you don't have any old ISA slots.
375	The "ISA Bus" exists in your computer even if you don't have ISA slots;
376	it is simply a memory-mapped area, 64KB in size (0x0000 - 0xFFFF)
377	where many "legacy" functions, such as keyboard and interrupt controllers,
378	are found. It isn't necessarily a separate physical bus.
379	See the file <code>/proc/ioports</code> for a list of devices living on
380	the "ISA Bus" in your system. If you don't like the term "ISA Bus"
381	think "I/O Space".
382
383	<p><hr>
384	Node:<a name="Section%202.4">Section 2.4</a>,
385	Next:<a rel=next accesskey=n href="#Section%202.5">Section 2.5</a>,
386	Previous:<a rel=previous accesskey=p href="#Section%202.3">Section 2.3</a>,
387	Up:<a rel=up accesskey=u href="#Basics">Basics</a>
388	<br>
389
390	<h3>2.4 What sensors do processors have?</h3>
391
392	<p>Most new processors contain a thermal diode on the die itself.
393	The electical properties of all diodes and transistors vary
394	slightly with temperature. The thermal diode is exceptionally accurate
395	because it is directly on the die. Newer temperature sensor chips,
396	like the Analog Devices ADM1021 and clones, and the Winbond chips,
397	have circuitry for measuring the the electrical properties of
398	an external diode and converting this data to a temperature.
399	Any sensor chip listed in <code>doc/chips/SUMMARY</code> in our package which
400	has support for more than one temperature supports external temperature sensing.
401
402	<p>Older motherboards and processors without this feature generally use
403	an LM75 placed close to the processor. This is much less accurate.
404
405	<p>The Pentium 2 'boxed' processor usually has an LM75 very close to the
406	base of the box. It can be read through the SMBus to report the approximate
407	temperature of the processor. The processor also contains an internal
408	temperature sensor (of low accuracy) used as a fail-safe to disable the
409	processor in case it gets much too hot (usually around 130 degrees C). And,
410	the Pentium 2 also has a hard-wired signal (VID lines) on it's SEC (single
411	edge connector) which indicates what power supply is required to operate the
412	processor.
413
414	<p>The P6 (Pentium-Pro) may have an LM75 in or just under the socket.
415	P6's also have VID lines.
416
417	<p>Pentiums and Pentium w/ MMX do not have VID lines, and sometimes have
418	LM75's under the sockets (depends on the mainboard, and how 'modern' the
419	mainboard is).
420
421	<p>The P2 Xeon was the first Intel processor to include the SMBus
422	interface on the P2 Xeon SEC.
423
424	<p><hr>
425	Node:<a name="Section%202.5">Section 2.5</a>,
426	Next:<a rel=next accesskey=n href="#Section%202.6">Section 2.6</a>,
427	Previous:<a rel=previous accesskey=p href="#Section%202.4">Section 2.4</a>,
428	Up:<a rel=up accesskey=u href="#Basics">Basics</a>
429	<br>
430
431	<h3>2.5 How often are the sensor values updated?</h3>
432
433	<p>The LM78, and most other sensor chips like it, reads its sensors one
434	by one. A complete scanning sweep will take about 1.5 seconds. The LM78 stops
435	readings sensors if you try to access it, so if you access it very often
436	(by reading sensor values; writing new limits is safe) it will not find the
437	time to update its sensor values at all! Fortunately, the kernel module takes
438	care not to do this, and only reads new values each 1.5 seconds. If you
439	read the values again, you will get the 'old' values again.
440
441	<p><hr>
442	Node:<a name="Section%202.6">Section 2.6</a>,
443	Previous:<a rel=previous accesskey=p href="#Section%202.5">Section 2.5</a>,
444	Up:<a rel=up accesskey=u href="#Basics">Basics</a>
445	<br>
446
447	<h3>2.6 How are alarms triggered?</h3>
448
449	<p>It is possible to monitor each sensor and have an alarm go off if
450	it crosses some pre-determined limits. There are two sorts of interrupts
451	which can be generated by sensor chips if this happens (it depends a bit on
452	the actual chip if both are supported; the LM80, for example, has only
453	IRQ interrupts): IRQ interrupts and SMI interrupts. IRQ stands for
454	Interrupt Request and are the interrupt lines you can find in <code>/proc/interrupts</code>.
455	SMI stands for System Management Interrupt, and is a special interrupt which
456	puts the processor in a secure environment independent of any other things
457	running. SMI is currently not supported by the Linux kernel. IRQs are
458	supported, of course.
459
460	<p>Even if no interrupt is generated, some bits in a status register
461	will be set until the register is read the next time. If the alarm condition
462	persists after that, the bits will be set on the next scanning sweep, etc.
463
464	<p>Most drivers in our package do not support interrupts at this time.
465
466	<p><hr>
467	Node:<a name="Installation">Installation</a>,
468	Next:<a rel=next accesskey=n href="#Problems">Problems</a>,
469	Previous:<a rel=previous accesskey=p href="#Basics">Basics</a>,
470	Up:<a rel=up accesskey=u href="#Top">Top</a>
471	<br>
472
473	<h2>3 Installation and Management</h2>
474
475	<ul>
476	<li><a accesskey=1 href="#Section%203.1">Section 3.1</a>: Why so many modules, and how do I cope with them?
477	<li><a accesskey=2 href="#Section%203.2">Section 3.2</a>: How do I know which chips I own?
478	<li><a accesskey=3 href="#Section%203.3">Section 3.3</a>: Which modules should I insert?
479	<li><a accesskey=4 href="#Section%203.4">Section 3.4</a>: Do I need the configuration file <code>/etc/sensors.conf</code>?
480	<li><a accesskey=5 href="#Section%203.5">Section 3.5</a>: What about the <code>No such file or directory</code> warnings
481	<li><a accesskey=6 href="#Section%203.6">Section 3.6</a>: I get all kinds of weird compilation errors?
482	<li><a accesskey=7 href="#Section%203.7">Section 3.7</a>: It still does not compile or patch!
483	<li><a accesskey=8 href="#Section%203.8">Section 3.8</a>: <code>make install</code> fails on Mandrake kernels
484	<li><a accesskey=9 href="#Section%203.9">Section 3.9</a>: I get unresolved symbols when I <code>modprobe</code> modules
485	<li><a href="#Section%203.10">Section 3.10</a>: I2C_DRIVERID_ADM1024 undefined (Red Hat especially)
486	</ul>
487
488	<p><hr>
489	Node:<a name="Section%203.1">Section 3.1</a>,
490	Next:<a rel=next accesskey=n href="#Section%203.2">Section 3.2</a>,
491	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
492	<br>
493
494	<h3>3.1 Why so many modules, and how do I cope with them?</h3>
495
496	<p>We tried to make this package as modular as possible. This makes it
497	easy to add new drivers, and unused drivers will take no precious kernel
498	space. On the other hand, it can be a bit confusing at first.
499
500	<p>Here are two simple guidelines:
501	<ul>
502	<li>Run <code>sensors-detect</code> and do what it tells you.
503	<li>Always use <code>modprobe</code>, not <code>insmod</code>.
504	</ul>
505
506	<p>Further information is in <code>doc/modules</code>.
507
508	<p><a name="How%20do%20I%20know%20which%20chips%20I%20own"></a>
509	<p><hr>
510	Node:<a name="Section%203.2">Section 3.2</a>,
511	Next:<a rel=next accesskey=n href="#Section%203.3">Section 3.3</a>,
512	Previous:<a rel=previous accesskey=p href="#Section%203.1">Section 3.1</a>,
513	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
514	<br>
515
516	<h3>3.2 How do I know which chips I own?</h3>
517
518	<p>We have an excellent program that scans all your hardware.
519	It is called <code>sensors-detect</code> and is installed in <code>/usr/local/sbin</code>
520	by <code>make install</code>. Just execute this script, and it will tell you.
521
522	<p>Chip detection in the drivers is fairly good. That means that it is
523	usually harmless to insert more chip drivers than you need. However, this
524	can still lead to problems, so we do not recommend it.
525
526	<p>If sensors-detect didn't find any sensors, either you don't have
527	any, or the ones you have, we don't support. (Look at your motherboard
528	for candidates, then see <a href="#Help">Help</a>)
529
530	<p><a name="Section%203.2.1"></a>
531
532	<h4>3.2.1 What chips are on motherboard XYZ?</h4>
533
534	<p><strong>!!!!!!!!! YES THIS IS THE MOST FREQUENT QUESTION WE GET !!!!!!!!!</strong>
535
536	<p>We have no idea. Here is what you should do:
537	<ol type=1 start=1>
538	</p><li>Run sensors-detect.
539	</ol>
540
541	<p>If that doesn't work:
542	<ol type=1 start=2>
543	</p><li>Look at your motherboard.
544	<li>Check the manufacturer's website or ask their support
545	<li>Check the <a href="http://mbm.livewiredev.com/">Motherboard Monitor</a> website and the
546	<a href="http://www2.lm-sensors.nu/~lm78/cvs/lm_sensors2/doc/useful_addresses.html">"links"</a>
547	page on <a href="http://www2.lm-sensors.nu/~lm78/">our website</a> some good cross-references.
548	</ol>
549
550	<p><a name="Section%203.2.2"></a>
551
552	<h4>3.2.2 Do you support motherboard XYZ?</h4>
553
554	<p>We don't support boards, we support chips. See <a href="#Section%203.2.1">What chips are on motherboard XYZ</a>.
555
556	<p><a name="Section%203.2.3"></a>
557
558	<h4>3.2.3 Do you support chip XYZ?</h4>
559
560	<p>This we have good answers for.
561	<ul>
562	<li>Sorted by Manufacturer: <code>README</code>
563	<li>Sorted by Manufacturer: <a href="http://www2.lm-sensors.nu/~lm78/supported.html">http://www2.lm-sensors.nu/~lm78/supported.html</a>
564	<li>Sorted by Sensor Driver: <code>doc/chips/SUMMARY</code>
565	<li>Newest Driver Status: <a href="http://www2.lm-sensors.nu/~lm78/newdrivers.html">http://www2.lm-sensors.nu/~lm78/newdrivers.html</a>
566	</ul>
567
568	<p><a name="Section%203.2.4"></a>
569
570	<h4>3.2.4 Anybody working on a driver for chip XYZ?</h4>
571
572	<p>Newest Driver Status: <a href="http://www2.lm-sensors.nu/~lm78/newdrivers.html">http://www2.lm-sensors.nu/~lm78/newdrivers.html</a>
573
574	<p><hr>
575	Node:<a name="Section%203.3">Section 3.3</a>,
576	Next:<a rel=next accesskey=n href="#Section%203.4">Section 3.4</a>,
577	Previous:<a rel=previous accesskey=p href="#Section%203.2">Section 3.2</a>,
578	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
579	<br>
580
581	<h3>3.3 Which modules should I insert?</h3>
582
583	<p><code>sensors-detect</code> will tell you. Take the <code>modprobe</code> lines it
584	recommends and paste them into the appropriate <code>/etc/rc.d/xxxx</code> file
585	to be executed at startup.
586
587	<p>You need one module for each sensor chip and bus adapter you own;
588	if there are sensor chips on the ISA bus, you also need <code>i2c-isa.o</code>.
589	for each type of chip you own. That's all. On my computer, I could use the
590	following lines:
591	<ul>
592	<li><code>modprobe i2c-isa</code>
593	<li><code>modprobe i2c-piix4</code>
594	<li><code>modprobe lm78</code>
595	<li><code>modprobe lm75</code>
596	<li><code>modprobe i2c-dev</code>
597	<li><code>sensors -s</code>
598	</ul>
599
600	<p><hr>
601	Node:<a name="Section%203.4">Section 3.4</a>,
602	Next:<a rel=next accesskey=n href="#Section%203.5">Section 3.5</a>,
603	Previous:<a rel=previous accesskey=p href="#Section%203.3">Section 3.3</a>,
604	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
605	<br>
606
607	<h3>3.4 Do I need the configuration file <code>/etc/sensors.conf</code>?</h3>
608
609	<p>Yes, for any applications that use <code>libsensors,</code> including the
610	<code>sensors</code> application included in our package.
611	It tells libsensors how to translate the values the chip
612	measures to real-world values. This is especially important for voltage
613	inputs. The default configuration file should usually do the trick.
614	It is automatically installed as <code>/etc/sensors.conf</code>, but it will not
615	overwrite any existing file with that name.
616
617	<p><a name="Section%203.4.1"></a>
618
619	<h4>3.4.1 The labels for the voltage and temperature readings in <code>sensors</code> are incorrect!</h4>
620
621	<p>Every motherboard is different. You can customize the labels
622	in the file <code>/etc/sensors.conf</code>. That's why it exists!
623	The default labelling (in <code>lib/chips.c</code> and <code>/etc/sensors.conf</code>) is just
624	a template.
625
626	<p><a name="Section%203.4.2"></a>
627
628	<h4>3.4.2 The min and max for the readings in <code>sensors</code> are incorrect!</h4>
629
630	<p>You can customize them in the file <code>/etc/sensors.conf</code>. See above.
631
632	<p><a name="Section%203.4.3"></a>
633
634	<h4>3.4.3 The min and max settings in <code>/etc/sensors.conf</code> didn't take effect!</h4>
635
636	<p>You forgot to run <code>sensors -s</code>. See above.
637
638	<p><a name="Section%203.4.4"></a>
639
640	<h4>3.4.4 One sensor isn't hooked up on my board!</h4>
641
642	<p>Use an <code>ignore</code> line in <code>/etc/sensors.conf</code> so it isn't
643	displayed in <code>sensors</code>.
644
645	<p><a name="Section%203.4.5"></a>
646
647	<h4>3.4.5 I need help with <code>sensors.conf</code>!</h4>
648
649	<p>There is detailed help at the top of that file.
650
651	<p><a name="Section%203.4.6"></a>
652
653	<h4>3.4.6 Do you have a database of <code>sensors.conf</code> entries for specific boards?</h4>
654
655	<p>No. Good idea though. If you would like to set one up on your website
656	send us mail and we will set up a link to it.
657
658	<p><hr>
659	Node:<a name="Section%203.5">Section 3.5</a>,
660	Next:<a rel=next accesskey=n href="#Section%203.6">Section 3.6</a>,
661	Previous:<a rel=previous accesskey=p href="#Section%203.4">Section 3.4</a>,
662	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
663	<br>
664
665	<h3>3.5 What about the <code>No such file or directory</code> warnings when I compile?</h3>
666
667	<p>Don't worry about them. The dependency files (which tell which
668	files should be recompiled when certain files change) are created
669	dynamically. They are not distributed with the package. The <code>make</code> program
670	notices they are not there, and warns about that - and the first thing
671	it will do is generate them. So all is well.
672
673	<p><hr>
674	Node:<a name="Section%203.6">Section 3.6</a>,
675	Next:<a rel=next accesskey=n href="#Section%203.7">Section 3.7</a>,
676	Previous:<a rel=previous accesskey=p href="#Section%203.5">Section 3.5</a>,
677	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
678	<br>
679
680	<h3>3.6 I get all kinds of weird compilation errors?</h3>
681
682	<p>Check that the correct i2c header files are used. Depending on
683	how you installed, they should be under either <code>/usr/local/include</code> or
684	<code>/usr/src/linux*/include</code>. Try to edit the <code>Makefile</code> for the other setting.
685
686	<p><a name="Section%203.6.1"></a>
687
688	<h4>3.6.1 <code>No rule to make target xxxx needed by xxxx</code> - how to fix?</h4>
689
690	<ul>
691	<li>See <a href="#Section%203.6">I get all kinds of weird compilation errors</a>, also try <code>make clean</code> in <code>lm_sensors</code>.
692	<li>If that doesn't work, try <code>make clean</code> in <code>i2c</code>.
693	<li>If that doesn't work, try <code>make clean</code> in the kernel.
694	<li>Also make sure <code>/usr/include/linux</code> points to <code>/usr/src/linux/include/linux</code>.
695	</ul>
696
697	<p><hr>
698	Node:<a name="Section%203.7">Section 3.7</a>,
699	Next:<a rel=next accesskey=n href="#Section%203.8">Section 3.8</a>,
700	Previous:<a rel=previous accesskey=p href="#Section%203.6">Section 3.6</a>,
701	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
702	<br>
703
704	<h3>3.7 It still does not compile or patch!</h3>
705
706	<p>Have you installed the matching version of the i2c package? Remember,
707	compilation is not enough, you also need to install it for the header
708	files to be found!
709
710	<p>If you want to patch the kernel, you will have to apply the i2c
711	patches first!
712
713	<p><hr>
714	Node:<a name="Section%203.8">Section 3.8</a>,
715	Next:<a rel=next accesskey=n href="#Section%203.9">Section 3.9</a>,
716	Previous:<a rel=previous accesskey=p href="#Section%203.7">Section 3.7</a>,
717	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
718	<br>
719
720	<h3>3.8 <code>make install</code> fails on Mandrake kernels</h3>
721
722	<p>Mandrake uses a non-standard <code>version.h</code> file which confuses our <code>Makefile</code>.
723	Edit our <code>Makefile</code> on the <code>MODDIR :=</code> line to hard-code the module directory.
724
725	<p><hr>
726	Node:<a name="Section%203.9">Section 3.9</a>,
727	Next:<a rel=next accesskey=n href="#Section%203.10">Section 3.10</a>,
728	Previous:<a rel=previous accesskey=p href="#Section%203.8">Section 3.8</a>,
729	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
730	<br>
731
732	<h3>3.9 I get unresolved symbols when I <code>modprobe</code> modules (Red Hat especially)</h3>
733
734	<p>Example:
735	<br><pre>*** Unresolved symbols in /lib/modules/2.4.5/kernel/drivers/i2c/i2c-i810.o
736	i2c_bit_add_bus_R8c3bc60e
737	i2c_bit_del_bus_R92b18f49
738	</pre>
739
740	<p>You can also run <code>depmod -a -e</code> to see all unresolved symbols.
741
742	<p>These are module versioning problems. Generally you did not compile
743	against the kernel you are running. Sometimes the Red Hat source you
744	have is not for the kernel you are running.
745	You must compile our package against the source for the kernel you
746	are running with something like <code>make LINUX=/usr/src/linux-2.4.14</code>.
747
748	<p>Try the following to be sure:
749
750	<ul>
751	<li><code>nm --extern MODULE.o</code>
752	Filter out the kernel symbols, like <code>kmalloc</code>, <code>printk</code> etc. and note the
753	number code behind them, like <code>printk_R1b7d4074</code>. If there is no numeric
754	code after them, note this too.
755	<li><code>grep SYMBOL /proc/ksyms</code>
756	Substitute SYMBOL by the basename of the symbols above, like <code>kmalloc</code>,
757	<code>printk</code> etc. Note the number code behind them, or the lack thereof.
758	<li>Compare both sets of symbols. Are they the same? If so, the problem
759	lies somewhere else. Are they different? If so, you have a module
760	versioning problem.
761	</ul>
762
763	<p><hr>
764	Node:<a name="Section%203.10">Section 3.10</a>,
765	Previous:<a rel=previous accesskey=p href="#Section%203.9">Section 3.9</a>,
766	Up:<a rel=up accesskey=u href="#Installation">Installation</a>
767	<br>
768
769	<h3>3.10 I2C_DRIVERID_ADM1024 undefined (Red Hat especially)</h3>
770
771	<p>In some versions of Redhat, an RPM is included to provide i2c support.
772	However, this RPM does not place the header files in the kernel directory
773	structure. When you update kernels, they may persist. To get rid of
774	these obsolete header files, at a command prompt:
775
776	<ol type=1 start=1>
777	</p><li><code>rpm -qa \| grep i2c</code>
778	<li>Look for <code>kernel-i2c,</code> or a similar rpm in the output
779	<li><as root>
780	<code>rpm -ev kernel-i2c</code> (or the name of the similar package)
781	If this complains about dependencies, you can try adding
782	<code>--nodeps</code>, but this MAY break something else. Not likely,
783	as you have upgraded kernels, and nothing should be using the
784	old i2c stuff anymore anyway. Just don't use it with abandon.
785	<li>Try (in the build directory of <code>lm_sensors)</code>
786	<br><pre><code>make clean</code>
787	<code>make</code>
788	</pre>
789	<li><em>If</em> you still have problems, you may have to replace the include
790	paths in the <code>.c/.h</code> files with absolute paths to the header files.
791	More of a workaround than a real fix, but at least you can get it
792	to work.
793	</ol>
794
795	<p><hr>
796	Node:<a name="Problems">Problems</a>,
797	Next:<a rel=next accesskey=n href="#Help">Help</a>,
798	Previous:<a rel=previous accesskey=p href="#Installation">Installation</a>,
799	Up:<a rel=up accesskey=u href="#Top">Top</a>
800	<br>
801
802	<h2>4 Problems</h2>
803
804	<ul>
805	<li><a accesskey=1 href="#Section%204.1">Section 4.1</a>: My fans report exactly half/double their values?
806	<li><a accesskey=2 href="#Section%204.2">Section 4.2</a>: Why do my two LM75's report "-48 degrees"?
807	<li><a accesskey=3 href="#Section%204.3">Section 4.3</a>: Why do I have two Vcore readings?
808	<li><a accesskey=4 href="#Section%204.4">Section 4.4</a>: How do those ALARMS work?
809	<li><a accesskey=5 href="#Section%204.5">Section 4.5</a>: My voltage readings seem to drift a bit. What's wrong?
810	<li><a accesskey=6 href="#Section%204.6">Section 4.6</a>: Some measurements are way out of range. What happened?
811	<li><a accesskey=7 href="#Section%204.7">Section 4.7</a>: What are VID lines? Why is the VID reading wrong?
812	<li><a accesskey=8 href="#Section%204.8">Section 4.8</a>: Sensor are only updated each second or so. Why?
813	<li><a accesskey=9 href="#Section%204.9">Section 4.9</a>: It takes a second before reading sensor results. Why?
814	<li><a href="#Section%204.10">Section 4.10</a>: Can I be alerted when an ALARM occurs?
815	<li><a href="#Section%204.11">Section 4.11</a>: SMBus transactions on my PIIX4 simply don't work. Why?
816	<li><a href="#Section%204.12">Section 4.12</a>: My BIOS reports a higher CPU temperature than you!
817	<li><a href="#Section%204.13">Section 4.13</a>: I read strange values from the raw <code>/proc</code> files!
818	<li><a href="#Section%204.14">Section 4.14</a>: How do I set new limits?
819	<li><a href="#Section%204.15">Section 4.15</a>: Some sensors are doubly detected?
820	<li><a href="#Section%204.16">Section 4.16</a>: I ran sensors-detect, but now I get strange readings?!
821	<li><a href="#Section%204.17">Section 4.17</a>: Bad readings from particular chips
822	<li><a href="#Section%204.18">Section 4.18</a>: How do I configure two chips (LM87) differently?
823	<li><a href="#Section%204.19">Section 4.19</a>: Dmesg says <code>Upgrade BIOS</code>! I don't want to!
824	<li><a href="#Section%204.20">Section 4.20</a>: Sensors says <code>Can't access <code>/proc</code> file</code>
825	<li><a href="#Section%204.21">Section 4.21</a>: Sensors says <code>No sensors found!</code>
826	<li><a href="#Section%204.22">Section 4.22</a>: Sensors output is not correct!
827	<li><a href="#Section%204.23">Section 4.23</a>: What is at I2C address XXX?
828	<li><a href="#Section%204.24">Section 4.24</a>: Sensors-detect doesn't work at all
829	<li><a href="#Section%204.25">Section 4.25</a>: Sensors says <code>Error: Line xxx: zzzzzzz</code>
830	<li><a href="#Section%204.26">Section 4.26</a>: Sensors only gives the name, adapter, and algorithm!
831	<li><a href="#Section%204.27">Section 4.27</a>: Sensors says <code>ERROR: Can't get xxxxx data!</code>
832	<li><a href="#Section%204.28">Section 4.28</a>: Sensors doesn't find any sensors, just eeproms.
833	<li><a href="#Section%204.29">Section 4.29</a>: Inserting modules hangs my board
834	<li><a href="#Section%204.30">Section 4.30</a>: Inserting modules slows down my board
835	<li><a href="#Section%204.31">Section 4.31</a>: Problems on particular motherboards
836	<li><a href="#Section%204.32">Section 4.32</a>: Problems on particular systems
837	</ul>
838
839	<p><hr>
840	Node:<a name="Section%204.1">Section 4.1</a>,
841	Next:<a rel=next accesskey=n href="#Section%204.2">Section 4.2</a>,
842	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
843	<br>
844
845	<h3>4.1 My fans report exactly half/double their values compared to the BIOS?</h3>
846
847	<p>The problem with much of the sensor data is that it is impossible to
848	properly interpret some of the readings without knowing what the hardware
849	configuration is. Some fans report one 'tick' each rotation, some report
850	two 'ticks' each rotation. It is easy to resolve this through the
851	configuration file <code>/etc/sensors.conf</code>:
852
853	<br><pre>chip lm78-* # Or whatever chip this relates to
854	compute fan1 2*@,@/2 # This will double the fan1 reading
855	# -- or --
856	compute fan1 @/2,2*@ # This will halve the fan1 reading
857	</pre>
858
859	<p>See <code>doc/fan-divisors</code> in our package for further information.
860
861	<p><a name="Fans%20sometimes%2falways%20read%200!"></a>
862
863	<h4>4.1.1 Fans sometimes/always read 0!!</h4>
864
865	<p>You may not have a three-wire fan, which is required.
866
867	<p>You may need to increase the 'fan divisor'. See <code>doc/fan-divisors</code>
868	in our package for further information.
869
870	<p><a name="I%20doubled%20the%20fan%20divisor%20and%20the%20fan%20still%20reads%207000"></a>
871
872	<h4>4.1.2 I doubled the fan divisor and the fan still reads 7000!</h4>
873
874	<p>Believe it or not, doubling the 'fan divisor' will not halve
875	the fan reading. You have to add a compute line in <code>/etc/sensors.conf</code>.
876	See <a href="#Section%204.1">My fans report exactly half/double their values compared to the BIOS</a>,
877	and see <code>doc/fan-divisors</code> in our package for further information.
878
879	<p><hr>
880	Node:<a name="Section%204.2">Section 4.2</a>,
881	Next:<a rel=next accesskey=n href="#Section%204.3">Section 4.3</a>,
882	Previous:<a rel=previous accesskey=p href="#Section%204.1">Section 4.1</a>,
883	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
884	<br>
885
886	<h3>4.2 Why do my two LM75's report "-48 degrees"?</h3>
887
888	<p>For starters, those aren't LM75's. Your mainboard actually has the
889	Winbond W83781D which emulates two LM75's, but many systems which use the
890	Winbond chip (such as the Asus P2B) don't have the thermo-resisters connected
891	to the chip resulting in these strange -48 degree readings.
892
893	<p>If you have an Asus P2B and want more information on adding thermal sensing capability, check out:
894	<a href="http://ultimatepc.fsn.net/techinfo/p2bthermistor/p2bthermistor.htm">http://ultimatepc.fsn.net/techinfo/p2bthermistor/p2bthermistor.htm</a>
895
896	<p>In upcoming versions, you will be able to disable non-interesting
897	readings.
898
899	<p><hr>
900	Node:<a name="Section%204.3">Section 4.3</a>,
901	Next:<a rel=next accesskey=n href="#Section%204.4">Section 4.4</a>,
902	Previous:<a rel=previous accesskey=p href="#Section%204.2">Section 4.2</a>,
903	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
904	<br>
905
906	<h3>4.3 Why do I have two Vcore readings, I have only one processor!</h3>
907
908	<p>The LM78 has seven voltage sensors. The default way of
909	connecting them is used in the configuration file. This includes a VCore2,
910	even if you do not have one. You can easily edit the configuration file
911	to give it another name, or make this reading disappear using
912	an <code>ignore</code> line.
913
914	<p>Note that Vcore2 is often the same as Vcore on motherboards which
915	only support one processor. Another possibility is that Vcore2 is not
916	connected at all and will not have a valid reading at all.
917	A third possibility, is that Vcore2 monitors something
918	else, so you should not be too surprised if the values are completely
919	different.
920
921	<p><hr>
922	Node:<a name="Section%204.4">Section 4.4</a>,
923	Next:<a rel=next accesskey=n href="#Section%204.5">Section 4.5</a>,
924	Previous:<a rel=previous accesskey=p href="#Section%204.3">Section 4.3</a>,
925	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
926	<br>
927
928	<h3>4.4 How do those ALARMS work? The current value is within range but there is still an ALARM warning!</h3>
929
930	<p>The ALARM indications in <code>sensors</code> are those reported by the
931	sensor chip itself. They are NOT calculated by <code>sensors</code>. <code>sensors</code>
932	simply reads the ALARM bits and reports them.
933
934	<p>An ALARM will go off when a minimum or maximum limit is crossed.
935	The ALARM is then latched - that is, it will stay there until the
936	chip's registers are next accessed - which will be the next time
937	you read these values, but not within (usually) 1.5 seconds since the last
938	update.
939
940	<p>Reading the registers clears the ALARMS, unless the current
941	value is still out of range.
942
943	<p>The purpose of this scheme is to tell you if there has been
944	a problem and report it to the user. Voltage or temperature spikes
945	get detected without having to read the sensor chip hundreds of times
946	a second. The implemetation details depend a bit on the kind of chip.
947	See the specific chip documentation in <code>doc/chips</code> and the
948	chip datasheet for more information.
949
950	<p><hr>
951	Node:<a name="Section%204.5">Section 4.5</a>,
952	Next:<a rel=next accesskey=n href="#Section%204.6">Section 4.6</a>,
953	Previous:<a rel=previous accesskey=p href="#Section%204.4">Section 4.4</a>,
954	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
955	<br>
956
957	<h3>4.5 My voltage readings seem to drift a bit. Is something wrong?</h3>
958
959	<p>No, probably not. If your motherboard heats up a bit, the sensed
960	voltages will drift a bit. If your power supply is loaded (because a disk
961	gets going, for example), the voltages may get a bit lower. Heavy
962	processor activity, in particular, dramatically increases core voltage
963	supply load which will often cause variation in the other supplies.
964	As long as they stay within a sensible range (say 5% of the nominal value
965	for CPU core voltages, and 10% for other voltages), there is no
966	reason to worry.
967
968	<p><hr>
969	Node:<a name="Section%204.6">Section 4.6</a>,
970	Next:<a rel=next accesskey=n href="#Section%204.7">Section 4.7</a>,
971	Previous:<a rel=previous accesskey=p href="#Section%204.5">Section 4.5</a>,
972	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
973	<br>
974
975	<h3>4.6 Some measurements are way out of range. What happened?</h3>
976
977	<p>Each module tries to set limits to sensible values on initialization,
978	but a module does not know how a chip is actually connected. This is
979	described in the configuration file, which is not read by kernel modules.
980	So limits can be strange, if the chip is connected in a non-standard way.
981
982	<p>Readings can also be strange; there are several reasons for this.
983	Temperature sensors, for example, can simply not be present, even though
984	the chip supports them. Also, it can be that the input is used in a
985	non-standard way. You can use the configuration file to describe how this
986	measurement should be interpreted; see the comments the example file for
987	more information.
988
989	<p><hr>
990	Node:<a name="Section%204.7">Section 4.7</a>,
991	Next:<a rel=next accesskey=n href="#Section%204.8">Section 4.8</a>,
992	Previous:<a rel=previous accesskey=p href="#Section%204.6">Section 4.6</a>,
993	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
994	<br>
995
996	<h3>4.7 What are VID lines? Why is the VID reading wrong?</h3>
997
998	<p>These describe the core voltage for your processor. They are
999	supported for most processors, however they are not always
1000	correctly connected to the sensor chip, so the readings may be invalid.
1001	A reading of 0V, +3.5V or +2.05V is especially suspect.
1002	If this is the case, add a line <code>ignore vid</code> to <code>/etc/sensors.conf</code>,
1003	and change the min and max settings for the Processor Core voltage
1004	(often in0_min and in0_max) in that file so that they don't depend on vid.
1005
1006	<p><hr>
1007	Node:<a name="Section%204.8">Section 4.8</a>,
1008	Next:<a rel=next accesskey=n href="#Section%204.9">Section 4.9</a>,
1009	Previous:<a rel=previous accesskey=p href="#Section%204.7">Section 4.7</a>,
1010	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1011	<br>
1012
1013	<h3>4.8 I read sensor values several times a second, but they are only updated only each second or so. Why?</h3>
1014
1015	<p>If we would read the registers more often, it would not find the
1016	time to update them. So we only update our readings once each 1.5 seconds
1017	(the actual delay is chip-specific; for some chips, it may not be needed
1018	at all).
1019
1020	<p><hr>
1021	Node:<a name="Section%204.9">Section 4.9</a>,
1022	Next:<a rel=next accesskey=n href="#Section%204.10">Section 4.10</a>,
1023	Previous:<a rel=previous accesskey=p href="#Section%204.8">Section 4.8</a>,
1024	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1025	<br>
1026
1027	<h3>4.9 It sometimes seems to take almost a second before I see the sensor reading results. Why?</h3>
1028
1029	<p>ISA bus access is fast, but SMBus access is really slow. If you have
1030	a lot of sensors, it just takes a lot of time to access them. Fortunately,
1031	this has almost no impact on the system as a whole, as another job can run
1032	while we are waiting for the transaction to finish.
1033
1034	<p><hr>
1035	Node:<a name="Section%204.10">Section 4.10</a>,
1036	Next:<a rel=next accesskey=n href="#Section%204.11">Section 4.11</a>,
1037	Previous:<a rel=previous accesskey=p href="#Section%204.9">Section 4.9</a>,
1038	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1039	<br>
1040
1041	<h3>4.10 Can I be alerted when an ALARM occurs?</h3>
1042
1043	<p>No, you can't; and it may well be never supported.
1044
1045	<p>Almost no mainboard we have encountered have actually connected the
1046	IRQ-out pin of sensor chips. That means that we could enable IRQ reporting, but
1047	nothing would happen. Also, even if a motherboard has it connected, it is
1048	unclear what interrupt number would be triggered. And IRQ lines are a scarce
1049	facility, which means that almost nobody would be able to use it anyway.
1050
1051	<p>The SMI interrupt is only available on a few types of chips. It is
1052	really a very obscure way to handle interrupts, and supporting it under Linux
1053	might be quite hard to do.
1054
1055	<p>Your best bet would be to poll the alarm file with a user-land daemon
1056	which alerts you if an alarm is raised. I am not aware of any program which
1057	does the job, though you might want to examine one of the graphical monitor
1058	programs 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.
1059
1060	<p><hr>
1061	Node:<a name="Section%204.11">Section 4.11</a>,
1062	Next:<a rel=next accesskey=n href="#Section%204.12">Section 4.12</a>,
1063	Previous:<a rel=previous accesskey=p href="#Section%204.10">Section 4.10</a>,
1064	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1065	<br>
1066
1067	<h3>4.11 SMBus transactions on my PIIX4 simply don't work (timeouts happen). Why?</h3>
1068
1069	<p>Some chips which mainboard makers connect to the SMBus are not SMBus
1070	devices. An example is the 91xx clock generator chips. When read, these
1071	devices can lock up the SMBus until the next hard reboot. This is because
1072	they have a similar serial interface (like the I2C), but don't conform to
1073	Intel's SMBus standard.
1074
1075	<p>Why did they connect these devices to the SMBus if they aren't
1076	compatible? Good question! :') Actually, these devices may support being
1077	written to, but lock things up when they are read.
1078
1079	<p><hr>
1080	Node:<a name="Section%204.12">Section 4.12</a>,
1081	Next:<a rel=next accesskey=n href="#Section%204.13">Section 4.13</a>,
1082	Previous:<a rel=previous accesskey=p href="#Section%204.11">Section 4.11</a>,
1083	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1084	<br>
1085
1086	<h3>4.12 My BIOS reports a much higher CPU temperature than your modules!</h3>
1087
1088	<p>We display the actual temperature of the sensor. This may not be the
1089	temperature you are interested in, though. If a sensor should measure
1090	the CPU temperature, it must be in thermal contact with it. In practice,
1091	it is just somewhere near it. Your BIOS may correct for this (by adding,
1092	for example, thirty degrees to the measured temperature). The correction
1093	factor is regrettably different for each mainboard, so we can not do this
1094	in the module itself. You can do it through the configuration file, though:
1095
1096	<br><pre>chip lm75-*-49 # Or whatever chip this relates to
1097	label temp "Processor"
1098	compute temp @*1.2+13,(@-13)/1.2 # Or whatever formula
1099	</pre>
1100
1101	<p><hr>
1102	Node:<a name="Section%204.13">Section 4.13</a>,
1103	Next:<a rel=next accesskey=n href="#Section%204.14">Section 4.14</a>,
1104	Previous:<a rel=previous accesskey=p href="#Section%204.12">Section 4.12</a>,
1105	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1106	<br>
1107
1108	<h3>4.13 I try to read the raw <code>/proc</code> files, but the values are strange?!?</h3>
1109
1110	<p>Remember, these values do not take the configuration file
1111	<code>compute</code> lines in account. This is especially obvious for voltage readings
1112	(usually called in? or vin?). Use a program linked to libsensors (like
1113	the provided <code>sensors</code> program) instead.
1114
1115	<p><hr>
1116	Node:<a name="Section%204.14">Section 4.14</a>,
1117	Next:<a rel=next accesskey=n href="#Section%204.15">Section 4.15</a>,
1118	Previous:<a rel=previous accesskey=p href="#Section%204.13">Section 4.13</a>,
1119	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1120	<br>
1121
1122	<h3>4.14 How do I set new limits?</h3>
1123
1124	<p>Change the limit values in <code>/etc/sensors.conf</code> and then run
1125	<code>sensors -s</code>.
1126
1127	<p><a name="I%20set%20new%20limits%20and%20it%20didnt%20work"></a>
1128
1129	<h4>4.14.1 I set new limits and it didn't work?</h4>
1130
1131	<p>You forgot to run <code>sensors -s</code>. Put it in a <code>/etc/rc.d/...</code> file
1132	after the modprobe lines to run at startup.
1133
1134	<p><hr>
1135	Node:<a name="Section%204.15">Section 4.15</a>,
1136	Next:<a rel=next accesskey=n href="#Section%204.16">Section 4.16</a>,
1137	Previous:<a rel=previous accesskey=p href="#Section%204.14">Section 4.14</a>,
1138	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1139	<br>
1140
1141	<h3>4.15 Some sensors are doubly detected?</h3>
1142
1143	<p>Yes, this is still a problem. It is partially solved by alias detection
1144	and confidence values in sensors-detect, but it is really tough.
1145
1146	<p>Double detections can be caused by two things:
1147	sensors can be detected to both the ISA and the SMBus (and if you have
1148	loaded the approprate adapter drivers, it will be detected on both), and
1149	some chips simulate other chips (the Winbond W83781D simulates LM75 chips
1150	on the SMBus, for example). Remove the offending adapter or chip driver, or
1151	run sensors-detect and add the <code>ignore=</code> modprobe parameters it suggests.
1152
1153	<p><hr>
1154	Node:<a name="Section%204.16">Section 4.16</a>,
1155	Next:<a rel=next accesskey=n href="#Section%204.17">Section 4.17</a>,
1156	Previous:<a rel=previous accesskey=p href="#Section%204.15">Section 4.15</a>,
1157	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1158	<br>
1159
1160	<h3>4.16 I ran sensors-detect, but now I get very strange readings?!?</h3>
1161
1162	<p>Your SMBus (PIIX4?) is probably crashed or hung. There are some mainboards
1163	which connect a clock chip to the SMBus. Unfortunately, this clock chip
1164	hangs the PIIX4 if it is read (it is an I2C device, but not SMBus compatible).
1165	We have found no way of solving this, except for rebooting your computer.
1166	Next time when you run sensors-detect, you may want to exclude addresses
1167	0x69 and/or 0x6a, by entering <kbd>s</kbd> when you are asked whether you want to
1168	scan the PIIX4.
1169
1170	<p><hr>
1171	Node:<a name="Section%204.17">Section 4.17</a>,
1172	Next:<a rel=next accesskey=n href="#Section%204.18">Section 4.18</a>,
1173	Previous:<a rel=previous accesskey=p href="#Section%204.16">Section 4.16</a>,
1174	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1175	<br>
1176
1177	<h3>4.17 Bad readings from particular chips</h3>
1178
1179	<p>See below for some particularly troublesome chips.
1180	Also be sure and check <code>doc/chips/xxxxx</code> for the particular driver.
1181
1182	<p><a name="Bad%20readings%20from%20the%20AS99127F"></a>
1183
1184	<h4>4.17.1 Bad readings from the AS99127F!</h4>
1185
1186	<p>The Asus AS99127F is a modified version of the Winbond W83781D.
1187	Asus will not release a datasheet. The driver was developed by tedious
1188	experimentation. We've done the best we can. If you want to make adjustments
1189	to the readings please edit <code>/etc/sensors.conf.</code> Please don't ask us to
1190	fix the driver. Ask Asus to release a datasheet.
1191
1192	<p><a name="Bad%20readings%20from%20the%20VIA%20686A"></a>
1193
1194	<h4>4.17.2 Bad readings from the VIA 686A!</h4>
1195
1196	<p>The Via 686A datasheet is incomplete.
1197	Via will not release details. The driver was developed by tedious
1198	experimentation. We've done the best we can. If you want to make adjustments
1199	to the readings please edit <code>/etc/sensors.conf.</code> Please don't ask us to
1200	fix the driver. Ask Via to release a better datasheet.
1201	Also, don't forget to <code>modprobe i2c-isa</code>.
1202
1203	<p><a name="Bad%20readings%20from%20the%20MTP008"></a>
1204
1205	<h4>4.17.3 Bad readings from the MTP008!</h4>
1206
1207	<p>The MTP008 has programmable temperature sensor types.
1208	If your sensor type does not match the default, you will have to change it.
1209	See <code>doc/chips/mtp008</code> for details.
1210	Also, MTP008 chips seem to randomly refuse to respond, for
1211	unknown reasons. You can see this as 'XX' entries in i2cdump.
1212
1213	<p><a name="Bad%20temperature%20readings%20from%20the%20SIS5595"></a>
1214
1215	<h4>4.17.4 Bad temperature readings from the SIS5595!</h4>
1216
1217	<p>This chip can use multiple thermistor types and there are also
1218	two different versions of the chip. We are trying to get the driver
1219	working better and develop formulas for different thermistors
1220	but we aren't there yet. Sorry.
1221	Also, many times the chip isn't really a sis5595 but it was
1222	misidentified. We are working on improving that too.
1223
1224	<p><a name="Bad%20readings%20from%20a%20w8378%5b12%5dd"></a>
1225
1226	<h4>4.17.5 Bad readings from a w8378[12]d!</h4>
1227
1228	<p>Do you own an ASUS motherboard? Perhaps your chip is being
1229	misidentified. Look on the motherboard (or at
1230	<a href="http://mbm.livewiredev.com">http://mbm.livewiredev.com</a>) for a 'Winbond' or Asus chip.
1231	Often the real device is an Asus as99127f. If so, the driver can be
1232	forced to recognize the as99127f with
1233	<code>force_as99127f=BUS,0x2d</code> where <code>BUS</code> is your i2c bus number.
1234	Cat /proc/bus/i2c to see a list of bus numbers.
1235	Read the w83781d module documentation (<code>doc/chips/w83781d</code>)
1236	for more details.
1237
1238	<p><a name="Bus%20hangs%20on%20Ali%201543%20on%20Asus%20P5A%20boards"></a>
1239
1240	<h4>4.17.6 Bus hangs on Ali 1543 on Asus P5A boards!</h4>
1241
1242	<p>The SMBus tends to hang on this board and it seems to get worse
1243	at higher temperatures. Use ISA accesses to reliably use the w83781d
1244	monitor chip on this board and use the <code>ignore=1,0x2d</code> or similar option
1245	to the w83781d module to prevent i2c accesses.
1246
1247	<p><a name="Bad%20readings%20from%20LM75"></a>
1248
1249	<h4>4.17.7 Bad readings from LM75!</h4>
1250
1251	<p>The LM75 detection is poor and other hardware is often misdetected
1252	as an LM75. Figure out what you really have See <a href="#Section%203.2.1">What chips are on motherboard XYZ</a>.
1253
1254	<p><a name="Bad%20readings%20from%20LM78"></a>
1255
1256	<h4>4.17.8 Bad readings from LM78!</h4>
1257
1258	<p>The LM78 is no longer manufactured by National Semiconductor.
1259	You probably don't have a real LM78 but something similar that we
1260	do not recogize or support. Figure out what you really have See <a href="#Section%203.2.1">What chips are on motherboard XYZ</a>.
1261
1262	<p><a name="Bad%20readings%20from%20LM80"></a>
1263
1264	<h4>4.17.9 Bad readings from LM80!</h4>
1265
1266	<p>The LM80 detection is poor and other hardware is often misdetected
1267	as an LM80. Figure out what you really have See <a href="#Section%203.2.1">What chips are on motherboard XYZ</a>.
1268
1269	<p><a name="Bad%20readings%20from%20it87"></a>
1270
1271	<h4>4.17.10 Bad readings from it87!</h4>
1272
1273	<p>The it87 temperature sesnsors are configured, unfortunately,
1274	in a way different from w83781d. They cannot be configured from
1275	<code>/etc/sensors.conf</code>; they must be set at modprobe insertion with
1276	<code>modprobe it87 temp_type=0xXX</code>. See <code>doc/chips/it87</code> for details.
1277
1278	<p><hr>
1279	Node:<a name="Section%204.18">Section 4.18</a>,
1280	Next:<a rel=next accesskey=n href="#Section%204.19">Section 4.19</a>,
1281	Previous:<a rel=previous accesskey=p href="#Section%204.17">Section 4.17</a>,
1282	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1283	<br>
1284
1285	<h3>4.18 How do I configure two chips (LM87) differently?</h3>
1286
1287	<p>There is a SuperMicro board with two LM87's on it that are
1288	not hooked up in the same way, so they need different defaults.
1289	For example, both CPU temperatures go to one LM87.
1290
1291	<p>Make two different sections in <code>/etc/sensors.conf</code> as follows:
1292	<br><pre>chip "lm87-i2c-*-2c"
1293	put configuration for the chip at 0x2c here
1294	chip "lm87-i2c-*-2d"
1295	put configuration for the chip at 0x2d here
1296	</pre>
1297
1298	<p>There is a commented example in <code>sensors.conf.eg</code> which should
1299	be helpful.
1300
1301	<p><hr>
1302	Node:<a name="Section%204.19">Section 4.19</a>,
1303	Next:<a rel=next accesskey=n href="#Section%204.20">Section 4.20</a>,
1304	Previous:<a rel=previous accesskey=p href="#Section%204.18">Section 4.18</a>,
1305	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1306	<br>
1307
1308	<h3>4.19 Dmesg says <code>Upgrade BIOS</code>! I don't want to!</h3>
1309
1310	<p>If the problem is a PCI device is not present in <code>lspci</code>, the solution
1311	is complex. For the ALI M7101 device, there is a solution which uses the
1312	2.4 kernel's <code>hotplug</code> facility. See <code>prog/hotplug</code> in our package.
1313	For other PCI devices, you can try to modify
1314	the m7101 solution in <code>prog/hotplug</code>.
1315
1316	<p>If dmesg says <code>try force_addr</code>, see below. Other drivers generally do not
1317	support the force_addr parameter. Sorry. Check the documentation
1318	for your driver in <code>doc/[chips,busses]</code> and if we don't support it
1319	you can send us your request.
1320
1321	<p><a name="Dmesg%20says%20use%20force_addr%3d0xaddr!%20What%20address%20do%20I%20use"></a>
1322
1323	<h4>4.19.1 Dmesg says <code>use force_addr=0xaddr</code>! What address do I use?</h4>
1324
1325	<p>If the problem is a PCI device whose base address is not set,
1326	you may be able to set the address with a force parameter. The via686a
1327	and sis5595 chip drivers, and some bus drivers, support the command line
1328	<code>modprobe via686a force_addr=0xADDRESS</code> where ADDRESS
1329	is the I/O address. You must select an address that is not in use.
1330	<code>cat <code>/proc/ioports</code></code> to check (carefully) for conflicts. A high number like
1331	0xf000 is generally safe.
1332
1333	<p><hr>
1334	Node:<a name="Section%204.20">Section 4.20</a>,
1335	Next:<a rel=next accesskey=n href="#Section%204.21">Section 4.21</a>,
1336	Previous:<a rel=previous accesskey=p href="#Section%204.19">Section 4.19</a>,
1337	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1338	<br>
1339
1340	<h3>4.20 Sensors says <code>Can't access <code>/proc</code> file</code></h3>
1341
1342	<ul>
1343	<li>(release 2.6.0 and later) Did you <code>modprobe i2c-proc</code>? Check <code>lsmod</code>.
1344	<li>(release 2.5.5 and earlier) Did you 'modprobe sensors'? Check 'lsmod'.
1345	<li>If you did <code>sensors -s</code>, did you run it as root?
1346	<li>Do you have <code>/proc</code> support in your kernel (is <code>/proc</code> there?)
1347	</ul>
1348
1349	<p><hr>
1350	Node:<a name="Section%204.21">Section 4.21</a>,
1351	Next:<a rel=next accesskey=n href="#Section%204.22">Section 4.22</a>,
1352	Previous:<a rel=previous accesskey=p href="#Section%204.20">Section 4.20</a>,
1353	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1354	<br>
1355
1356	<h3>4.21 Sensors says <code>No sensors found!</code></h3>
1357
1358	<ul>
1359	<li>Did <code>sensors-detect</code> find sensors? (If not see <a href="#Sensors-detect%20doesnt%20find%20any%20sensors">Sensors-detect doesnt find any sensors</a>)
1360	<li>Did you do what <code>sensors-detect</code> said?
1361	<li>Did you <code>modprobe</code> your sensor modules?
1362	<li>Did you <code>modprobe</code> your I2C adapter modules?
1363	<li>Did you <code>modprobe i2c-isa</code> if you have ISA sensor chips?
1364	<li>Check <code>lsmod</code>.
1365	</ul>
1366
1367	<p><hr>
1368	Node:<a name="Section%204.22">Section 4.22</a>,
1369	Next:<a rel=next accesskey=n href="#Section%204.23">Section 4.23</a>,
1370	Previous:<a rel=previous accesskey=p href="#Section%204.21">Section 4.21</a>,
1371	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1372	<br>
1373
1374	<h3>4.22 Sensors output is not correct!</h3>
1375
1376	<p>What specifically is the trouble?
1377	<ul>
1378	<li>Labels: See <a href="#Section%203.4.1">The labels for the voltage and temperature readings in sensors are incorrect</a>.
1379	<li>Min/max readings: See <a href="#Section%203.4.2">The min and max for the readings in sensors are incorrect</a>, and See <a href="#Section%203.4.3">The min and max settings didnt take effect</a>.
1380	<li>AS99127F: See <a href="#Section%204.16">I ran sensors-detect but now I get very strange readings?</a>.
1381	<li>Via 686A: See <a href="#Section%204.16">I ran sensors-detect but now I get very strange readings?</a>.
1382	<li>Other specific chips: See <a href="#Section%204.16">I ran sensors-detect but now I get very strange readings?</a>.
1383	<li>No output for a particular sensors chip: See <a href="#Section%205.3">What to do if it inserts but nothing happens</a>.
1384	<li>No output at all: See <a href="#Section%204.21">Sensors says No sensors found</a>, See <a href="#Section%205.3">What to do if it inserts but nothing happens</a>.
1385	<li>Completely bad output for a particular sensor chip: See <a href="#Section%205.4">What to do if I read only bogus information</a>.
1386	<li>One particular sensor readings:
1387	<ul>
1388	<li>Maybe it isn't hooked up? - tell 'sensors' to ignore it. See <a href="#Section%203.4.4">One sensor isnt hooked up on my board</a>.
1389	<li>Maybe it is hooked up differently on your motherboard? - adjust <code>sensors.conf</code> calculation.
1390	</ul>
1391	</ul>
1392
1393	<p><hr>
1394	Node:<a name="Section%204.23">Section 4.23</a>,
1395	Next:<a rel=next accesskey=n href="#Section%204.24">Section 4.24</a>,
1396	Previous:<a rel=previous accesskey=p href="#Section%204.22">Section 4.22</a>,
1397	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1398	<br>
1399
1400	<h3>4.23 What is at I2C address XXX?</h3>
1401
1402	<p>In general, we don't know. Start by running <code>sensors-detect</code>.
1403	If it doesn't recognize it, try running <code>i2cdump</code>. A partial list
1404	of manufacturers' IDs are at the bottom of <code>doc/chips/SUMMARY</code>.
1405
1406	<p><a name="What%20is%20at%20I2C%20address%200x69"></a>
1407
1408	<h4>4.23.1 What is at I2C address 0x69?</h4>
1409
1410	<p>A clock chip. Often, accessing these clock chips in the wrong
1411	way will instantly crash your computer. Sensors-detect carefully
1412	avoids these chips. If you really really want to play with your clock
1413	chip you can look at <code>kernel/chips/icspll.c</code> in our package. But we
1414	do not recommend it. You have been warned.
1415
1416	<p><a name="What%20is%20at%20I2C%20addresses%200x50%20-%200x57"></a>
1417
1418	<h4>4.23.2 What is at I2C addresses 0x50 - 0x57?</h4>
1419
1420	<p>EEPROMs on your SDRAM DIMMs. Load the eeprom module to
1421	look at some basic data in <code>sensors</code> or use the program
1422	<code>prog/eeprom/decode-dimms.pl</code> to get more information than you ever wanted.
1423
1424	<p><a name="What%20is%20at%20I2C%20addresses%200x30%20-%200x37"></a>
1425
1426	<h4>4.23.3 What is at I2C addresses 0x30 - 0x37?</h4>
1427
1428	<p>These are often 'shadows' of your EEPROMs on your SDRAM DIMMs
1429	at addresses 0x50 - 0x57. They aren't really there. If you try and
1430	do a <code>i2cdump</code> on them you won't get anything. This is probably
1431	caused by some timing problem on your motherboard or on the DIMMs.
1432	We don't know the exact cause.
1433
1434	<p><hr>
1435	Node:<a name="Section%204.24">Section 4.24</a>,
1436	Next:<a rel=next accesskey=n href="#Section%204.25">Section 4.25</a>,
1437	Previous:<a rel=previous accesskey=p href="#Section%204.23">Section 4.23</a>,
1438	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1439	<br>
1440
1441	<h3>4.24 Sensors-detect doesn't work at all</h3>
1442
1443	<p>It could be many things. What was the problem? See <a href="#Section%204.31">Problems on particular motherboards</a>.
1444
1445	<p><a name="Sensors-detect%20says%20%22Couldnt%20open%20%2fproc%2fbus%2fi2c%3f!%3f%22"></a>
1446
1447	<h4>4.24.1 Sensors-detect says "Couldn't open /proc/bus/i2c?!?"</h4>
1448
1449	<p>You don't have i2c support in your kernel, or the i2c-core module
1450	was not loaded and you did not run sensors-detect as root.
1451
1452	<p><a name="Sensors-detect%20says%20%22Cant%20open%20%2fdev%2fi2c%5b-%2f%5d0%22"></a>
1453
1454	<h4>4.24.2 Sensors-detect says "Can't open /dev/i2c[-/]0"</h4>
1455
1456	<p>Your <code>/dev/i2c-0,</code> <code>/dev/i2c0</code>, or <code>/dev/i2c/0</code> files do not exist
1457	or you did not run <code>sensors-detect</code> as root.
1458	Run the script <code>prog/mkdev/mkdev.sh</code> to create the <code>/dev/i2c-x</code> files.
1459	Run <code>devfs</code> in the kernel to get the <code>/dev/i2c/x</code> files.
1460
1461	<p><a name="Sensors-detect%20doesnt%20find%20any%20sensors"></a>
1462
1463	<h4>4.24.3 Sensors-detect doesn't find any sensors!</h4>
1464
1465	<p>Either
1466	<ol type=1 start=1>
1467	</p><li>The board doesn't have any sensors.
1468	<li>We don't support the sensors on the board.
1469	<li>The sensors it has are on an I2C bus connected to an I2C bus adapter that we don't support.
1470	<li>You don't have the latest version of lm_sensors.
1471	</ol>
1472
1473	<p>But in any case you should figure out what is on the board:
1474	<ol type=1 start=1>
1475	</p><li>Look at your motherboard.
1476	<li>Check the manufacturer's website.
1477	<li>Check the <a href="http://mbm.livewiredev.com/">Motherboard Monitor</a> website.
1478	</ol>
1479
1480	<p>When you know what chips you have, check the
1481	<a href="http://www2.lm-sensors.nu/~lm78/newdrivers.html">Newest Driver Status</a> web page to
1482	see if support has been added for your chip in a later release or in CVS.
1483
1484	<p><hr>
1485	Node:<a name="Section%204.25">Section 4.25</a>,
1486	Next:<a rel=next accesskey=n href="#Section%204.26">Section 4.26</a>,
1487	Previous:<a rel=previous accesskey=p href="#Section%204.24">Section 4.24</a>,
1488	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1489	<br>
1490
1491	<h3>4.25 Sensors says <code>Error: Line xxx: zzzzzzz</code></h3>
1492
1493	<p>These are errors from the libsensors library in
1494	reading the <code>/etc/sensors.conf</code> configuration file. Go to that line
1495	number and fix it. If you have a parse error, perhaps you have
1496	to put the feature name in double quotes.
1497
1498	<p><hr>
1499	Node:<a name="Section%204.26">Section 4.26</a>,
1500	Next:<a rel=next accesskey=n href="#Section%204.27">Section 4.27</a>,
1501	Previous:<a rel=previous accesskey=p href="#Section%204.25">Section 4.25</a>,
1502	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1503	<br>
1504
1505	<h3>4.26 Sensors only gives the name, adapter, and algorithm for my chip</h3>
1506
1507	<p>If <code>sensors</code> only says this, for example, and doesn't
1508	provide any actual data at all:
1509
1510	<br><pre>it87-isa-0290
1511	Adapter: ISA adapter
1512	Algorithm: ISA algorithm
1513	</pre>
1514
1515	<p>Your chip is not currently supported by <code>sensors</code> and so all it
1516	does is print out that information. Get the latest release
1517	and be sure you are running the <code>sensors</code> program it installed
1518	and not some older <code>sensors</code>.
1519
1520	<p><hr>
1521	Node:<a name="Section%204.27">Section 4.27</a>,
1522	Next:<a rel=next accesskey=n href="#Section%204.28">Section 4.28</a>,
1523	Previous:<a rel=previous accesskey=p href="#Section%204.26">Section 4.26</a>,
1524	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1525	<br>
1526
1527	<h3>4.27 Sensors says <code>ERROR: Can't get xxxxx data!</code></h3>
1528
1529	<p>You have a <code>libsensors/sensors</code> mismatch. <code>sensors</code> is unable to
1530	get a data entry from <code>libsensors</code>. You probably have an
1531	old <code>libsensors</code> in your <code>/etc/ld.so.conf</code> path.
1532	Make sure you did (as root) a <code>make install</code> followed by a <code>ldconfig</code>.
1533	Then check the output of <code>ldconfig -v \| grep libsensors</code> to
1534	verify that there is only ONE <code>libsensors</code> entry and that it matches
1535	the <code>libsensors</code> that was built in the <code>lib/</code> directory in <code>lm_sensors2</code>.
1536
1537	<p><hr>
1538	Node:<a name="Section%204.28">Section 4.28</a>,
1539	Next:<a rel=next accesskey=n href="#Section%204.29">Section 4.29</a>,
1540	Previous:<a rel=previous accesskey=p href="#Section%204.27">Section 4.27</a>,
1541	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1542	<br>
1543
1544	<h3>4.28 Sensors doesn't find any sensors, just eeproms.</h3>
1545
1546	<p>See <a href="#Section%204.24">Sensors-detect doesnt work at all</a>, if <code>sensors-detect</code> failed to find any sensors.
1547
1548	<p>If <code>sensors-detect</code> did find sensors, did you insert your modules? For chips on the ISA
1549	bus, did you insert i2c-isa?
1550
1551	<p>See <a href="#Section%205.2">What to do if a module wont insert</a>, if the modules didn't insert,
1552	also <a href="#Section%204.21">Sensors says No sensors found</a>.
1553
1554	<p><hr>
1555	Node:<a name="Section%204.29">Section 4.29</a>,
1556	Next:<a rel=next accesskey=n href="#Section%204.30">Section 4.30</a>,
1557	Previous:<a rel=previous accesskey=p href="#Section%204.28">Section 4.28</a>,
1558	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1559	<br>
1560
1561	<h3>4.29 Inserting modules hangs my board</h3>
1562
1563	<p>There are several possible causes:
1564	<ol type=1 start=1>
1565	</p><li>Bus driver problems. Insert the bus driver first, before you have inserted any chip drivers, to verify.
1566	<li>Wrong chip driver. Verify that you have a chip supported by the chip driver, see <a href="#Section%203.2.1">What chips are on motherboard XYZ</a>.
1567	<li>The chip driver is reinitializing the chip, which undoes critical initialization done by the BIOS. Try the parameter <code>init=0</code> for the w83781d driver; this is the only driver supporting this parameter.
1568	<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 <code>i2cdetect</code> on the bus, then <code>i2cdump</code> on each address responding to <code>i2cdetect</code>. This may find the culprit. Do not <code>i2cdump address 0x69</code>, the clock chip.
1569	<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 <code>modprobe ignore_range=0,0x00,0x28,0,0x2a,0x7f</code> to prevent access to other addresses. (<code>init=0</code> also req'd for the Tyan 2688).
1570	</ol>
1571
1572	<p><hr>
1573	Node:<a name="Section%204.30">Section 4.30</a>,
1574	Next:<a rel=next accesskey=n href="#Section%204.31">Section 4.31</a>,
1575	Previous:<a rel=previous accesskey=p href="#Section%204.29">Section 4.29</a>,
1576	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1577	<br>
1578
1579	<h3>4.30 Inserting modules slows down my board</h3>
1580
1581	<p>Generally this is caused by an overtemperature alarm output from
1582	the sensor chip. This triggers hardware on the board which
1583	automatically slows down the CPU clock. Be sure that your
1584	temperature limits are above the temperature reading. Put
1585	the new limits in <code>/etc/sensors.conf</code> and run <code>sensors -s</code>.
1586
1587	<p><hr>
1588	Node:<a name="Section%204.31">Section 4.31</a>,
1589	Next:<a rel=next accesskey=n href="#Section%204.32">Section 4.32</a>,
1590	Previous:<a rel=previous accesskey=p href="#Section%204.30">Section 4.30</a>,
1591	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1592	<br>
1593
1594	<h3>4.31 Problems on particular motherboards</h3>
1595
1596	<p>The following boards have unique problems and solutions.
1597
1598	<p><a name="Asus%20P4B"></a>
1599
1600	<h4>4.31.1 Asus P4B</h4>
1601
1602	<p>See <code>prog/hotplug/README.p4b</code> if your SMBus master is not found.
1603
1604	<p><a name="Tyan%202460%202462"></a>
1605
1606	<h4>4.31.2 Tyan 2460, 2462</h4>
1607
1608	<p>See support tickets 805, 765, 781, 812, 813, and 867 for information.
1609
1610	<p><a name="Tyan%202466"></a>
1611
1612	<h4>4.31.3 Tyan 2466</h4>
1613
1614	<p>See support tickets 941, 840, and 841 for information.
1615
1616	<p><a name="Tyan%202688"></a>
1617
1618	<h4>4.31.4 Tyan 2688</h4>
1619
1620	<p>For board hangs, see support ticket 721 for information.
1621	Also <a href="#Section%204.29">Inserting modules hangs my board</a>.
1622
1623	<p><hr>
1624	Node:<a name="Section%204.32">Section 4.32</a>,
1625	Previous:<a rel=previous accesskey=p href="#Section%204.31">Section 4.31</a>,
1626	Up:<a rel=up accesskey=u href="#Problems">Problems</a>
1627	<br>
1628
1629	<h3>4.32 Problems on particular systems</h3>
1630
1631	<p>For IBM systems, see <code>README.thinkpad</code>.
1632
1633	<p><hr>
1634	Node:<a name="Help">Help</a>,
1635	Next:<a rel=next accesskey=n href="#Contribute">Contribute</a>,
1636	Previous:<a rel=previous accesskey=p href="#Problems">Problems</a>,
1637	Up:<a rel=up accesskey=u href="#Top">Top</a>
1638	<br>
1639
1640	<h2>5 How to Ask for Help</h2>
1641
1642	<ul>
1643	<li><a accesskey=1 href="#Section%205.1">Section 5.1</a>: What to send us when asking for help
1644	<li><a accesskey=2 href="#Section%205.2">Section 5.2</a>: What to do if a module won't insert?
1645	<li><a accesskey=3 href="#Section%205.3">Section 5.3</a>: What to do if it inserts, but nothing happens?
1646	<li><a accesskey=4 href="#Section%205.4">Section 5.4</a>: What to do if I read only bogus information?
1647	<li><a accesskey=5 href="#Section%205.5">Section 5.5</a>: What to do if you have other problems?
1648	<li><a accesskey=6 href="#Section%205.6">Section 5.6</a>: What if it just works like a charm?
1649	<li><a accesskey=7 href="#Section%205.7">Section 5.7</a>: How do I update a ticket?
1650	<li><a accesskey=8 href="#Section%205.8">Section 5.8</a>: How do I follow up on a ticket?
1651	</ul>
1652
1653	<p><hr>
1654	Node:<a name="Section%205.1">Section 5.1</a>,
1655	Next:<a rel=next accesskey=n href="#Section%205.2">Section 5.2</a>,
1656	Up:<a rel=up accesskey=u href="#Help">Help</a>
1657	<br>
1658
1659	<h3>5.1 What to send us when asking for help</h3>
1660
1661	<p>We are always willing to answer questions if things don't work out.
1662	Please email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>, and not the individual authors,
1663	unless you have something private to say.
1664
1665	<p>Instead of using email, you can also use the web-based support
1666	area, at <a href="http://secure.netroedge.com/~lm78/support.html">http://secure.netroedge.com/~lm78/support.html</a>. You will be helped
1667	just as fast, and others may profit from the answer too. You will be
1668	emailed automatically when your question has been answered.
1669
1670	<p>Here's what you should send us:
1671
1672	<ul>
1673	<li>The dmesg or syslog output if applicable
1674	<li>The output of (as root) <code>prog/detect/sensors-detect</code>
1675	<li>The output of <code>lsmod</code>
1676	<li>If a PCI chip problem:
1677	<ul>
1678	<li>The output of <code>lspci -n</code>
1679	</ul>
1680	<li>If an I2C sensor chip problem:
1681	<ul>
1682	<li>The output of (as root) <code>prog/detect/i2cdetect X</code>
1683	where X = the bus number (run <code>i2cdetect</code> with no arguments to list the busses)
1684	(please send this only if it's not all <code>XX</code>)
1685	<li>The output of (as root) <code>prog/dump/i2cdump X 0xXX</code>
1686	where XX = the address of each chip you see in the output of <code>i2cdetect</code>. (run once for each chip)
1687	(please send this only if it's not all <code>ff</code>)
1688	</ul>
1689	<li>If an ISA sensor chip problem:
1690	<ul>
1691	<li>The output of (as root) <code>prog/dump/isadump 0x295 0x296</code> (only if it's not all <code>XX</code>)
1692	</ul>
1693	<li>Part numbers of chips on your motherboard you think are the sensor chips (look at your motherboard)
1694	<li>Motherboard type
1695	<li>Sensors version
1696	<li>Kernel version
1697	</ul>
1698
1699	<p><hr>
1700	Node:<a name="Section%205.2">Section 5.2</a>,
1701	Next:<a rel=next accesskey=n href="#Section%205.3">Section 5.3</a>,
1702	Previous:<a rel=previous accesskey=p href="#Section%205.1">Section 5.1</a>,
1703	Up:<a rel=up accesskey=u href="#Help">Help</a>
1704	<br>
1705
1706	<h3>5.2 What to do if a module won't insert?</h3>
1707
1708	<p>Did you use <code>modprobe</code> instead of <code>insmod</code>??? Don't use insmod.
1709
1710	<p>Were there unresolved symbols? Did you run <code>depmod -a</code>? Run
1711	<code>depmod -a -e</code> to see where the symbol problem is.
1712
1713	<p>ALWAYS inspect the output of <code>dmesg</code>. That's where the error
1714	messages come out!!! Don't rely on the generic message from <code>modprobe</code>.
1715	If you still can't figure it out, send us the information
1716	listed above.
1717
1718	<p><hr>
1719	Node:<a name="Section%205.3">Section 5.3</a>,
1720	Next:<a rel=next accesskey=n href="#Section%205.4">Section 5.4</a>,
1721	Previous:<a rel=previous accesskey=p href="#Section%205.2">Section 5.2</a>,
1722	Up:<a rel=up accesskey=u href="#Help">Help</a>
1723	<br>
1724
1725	<h3>5.3 What to do if it inserts, but nothing happens?</h3>
1726
1727	<p>For an ISA sensor chip, did you also <code>modprobe i2c-isa</code>? It must be inserted.
1728
1729	<p>For an I2C sensor chip, did you also <code>modprobe i2c-xxx</code> where xxx is your
1730	I2C bus adapter? It must be inserted.
1731
1732	<p>Always inspect the output of <code>dmesg</code>. That's where the error
1733	messages come out. If you still can't figure it out, send us the information
1734	listed above.
1735
1736	<p><hr>
1737	Node:<a name="Section%205.4">Section 5.4</a>,
1738	Next:<a rel=next accesskey=n href="#Section%205.5">Section 5.5</a>,
1739	Previous:<a rel=previous accesskey=p href="#Section%205.3">Section 5.3</a>,
1740	Up:<a rel=up accesskey=u href="#Help">Help</a>
1741	<br>
1742
1743	<h3>5.4 What to do if I read only bogus information?</h3>
1744
1745	<p>It may be that this was a mis-detection: the chip may not be
1746	present. If you are convinced there is something wrong, verify that you
1747	indeed have the devices on your motherboard that you think you do.
1748	Look at the motherboard and make sure. If you are still stuck,
1749	please send us the usual information (see <a href="#Help">Help</a>)
1750
1751	<p><hr>
1752	Node:<a name="Section%205.5">Section 5.5</a>,
1753	Next:<a rel=next accesskey=n href="#Section%205.6">Section 5.6</a>,
1754	Previous:<a rel=previous accesskey=p href="#Section%205.4">Section 5.4</a>,
1755	Up:<a rel=up accesskey=u href="#Help">Help</a>
1756	<br>
1757
1758	<h3>5.5 What to do if you have other problems?</h3>
1759
1760	<p>Again, send the output listed above.
1761
1762	<p><hr>
1763	Node:<a name="Section%205.6">Section 5.6</a>,
1764	Next:<a rel=next accesskey=n href="#Section%205.7">Section 5.7</a>,
1765	Previous:<a rel=previous accesskey=p href="#Section%205.5">Section 5.5</a>,
1766	Up:<a rel=up accesskey=u href="#Help">Help</a>
1767	<br>
1768
1769	<h3>5.6 What if it just works like a charm?</h3>
1770
1771	<p>Drop us a mail if you feel like it, mentioning the mainboard and
1772	detected chip type. That way, we have some positive feedback, too!
1773
1774	<p><hr>
1775	Node:<a name="Section%205.7">Section 5.7</a>,
1776	Next:<a rel=next accesskey=n href="#Section%205.8">Section 5.8</a>,
1777	Previous:<a rel=previous accesskey=p href="#Section%205.6">Section 5.6</a>,
1778	Up:<a rel=up accesskey=u href="#Help">Help</a>
1779	<br>
1780
1781	<h3>5.7 How do I update a ticket?</h3>
1782
1783	<p>You can't. Only developers can. Follow up by emailing us
1784	at <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a> and reference your ticket number
1785	in the subject. Please don't enter a new ticket with
1786	follow-up information, email us instead. Thanks.
1787
1788	<p><hr>
1789	Node:<a name="Section%205.8">Section 5.8</a>,
1790	Previous:<a rel=previous accesskey=p href="#Section%205.7">Section 5.7</a>,
1791	Up:<a rel=up accesskey=u href="#Help">Help</a>
1792	<br>
1793
1794	<h3>5.8 How do I follow up on a ticket?</h3>
1795
1796	<p>Follow up by emailing us at <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>
1797	and reference your ticket number in the subject.
1798
1799	<p><hr>
1800	Node:<a name="Contribute">Contribute</a>,
1801	Next:<a rel=next accesskey=n href="#Version%201%20Specifics">Version 1 Specifics</a>,
1802	Previous:<a rel=previous accesskey=p href="#Help">Help</a>,
1803	Up:<a rel=up accesskey=u href="#Top">Top</a>
1804	<br>
1805
1806	<h2>6 How to Contribute</h2>
1807
1808	<ul>
1809	<li><a accesskey=1 href="#Section%206.1">Section 6.1</a>: How to write a driver
1810	<li><a accesskey=2 href="#Section%206.2">Section 6.2</a>: How to get CVS access
1811	<li><a accesskey=3 href="#Section%206.3">Section 6.3</a>: How to donate hardware to the project
1812	<li><a accesskey=4 href="#Section%206.4">Section 6.4</a>: How to join the project mailing list
1813	<li><a accesskey=5 href="#Section%206.5">Section 6.5</a>: How to access mailing list archives
1814	<li><a accesskey=6 href="#Section%206.6">Section 6.6</a>: How to submit a patch
1815	<li><a accesskey=7 href="#Section%206.7">Section 6.7</a>: How to REALLY help
1816	<li><a accesskey=8 href="#Section%206.8">Section 6.8</a>: How to get release announcements
1817	<li><a accesskey=9 href="#Section%206.9">Section 6.9</a>: How to block spam on the project mailing list
1818	</ul>
1819
1820	<p><hr>
1821	Node:<a name="Section%206.1">Section 6.1</a>,
1822	Next:<a rel=next accesskey=n href="#Section%206.2">Section 6.2</a>,
1823	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1824	<br>
1825
1826	<h3>6.1 How to write a driver</h3>
1827
1828	<p>See <code>doc/developers/new_drivers</code> in our package for instructions.
1829
1830	<p><hr>
1831	Node:<a name="Section%206.2">Section 6.2</a>,
1832	Next:<a rel=next accesskey=n href="#Section%206.3">Section 6.3</a>,
1833	Previous:<a rel=previous accesskey=p href="#Section%206.1">Section 6.1</a>,
1834	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1835	<br>
1836
1837	<h3>6.2 How to get CVS access</h3>
1838
1839	<p>For anonymous CVS read access, see the instructions on our download page.
1840	Sorry, we don't have automatically generated CVS tarballs.
1841
1842	<p>For write access, run the script <code>doc/developers/genpasswd.pl</code> in
1843	our package and follow the instructions. Let us know what part
1844	of the package you would like to work on.
1845
1846	<p><hr>
1847	Node:<a name="Section%206.3">Section 6.3</a>,
1848	Next:<a rel=next accesskey=n href="#Section%206.4">Section 6.4</a>,
1849	Previous:<a rel=previous accesskey=p href="#Section%206.2">Section 6.2</a>,
1850	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1851	<br>
1852
1853	<h3>6.3 How to donate hardware to the project</h3>
1854
1855	<p>Send us email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>.
1856
1857	<p><hr>
1858	Node:<a name="Section%206.4">Section 6.4</a>,
1859	Next:<a rel=next accesskey=n href="#Section%206.5">Section 6.5</a>,
1860	Previous:<a rel=previous accesskey=p href="#Section%206.3">Section 6.3</a>,
1861	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1862	<br>
1863
1864	<h3>6.4 How to join the project mailing list</h3>
1865
1866	<p>Send us email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a>. Sorry,
1867	there is no automated subscribe/unsubscribe service yet
1868	(but we're seriously thinking of switching to majordomo).
1869	Please note that you do NOT need to be subscribed to the list
1870	in order to post. If you simply need help as a user, post your
1871	detailed problem and questions directly. Don't worry, you'll be
1872	CC'd on all replies.
1873
1874	<p><hr>
1875	Node:<a name="Section%206.5">Section 6.5</a>,
1876	Next:<a rel=next accesskey=n href="#Section%206.6">Section 6.6</a>,
1877	Previous:<a rel=previous accesskey=p href="#Section%206.4">Section 6.4</a>,
1878	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1879	<br>
1880
1881	<h3>6.5 How to access mailing list archives</h3>
1882
1883	<p>The mailing list archive is at: <a href="http://archives.andrew.net.au/lm-sensors">http://archives.andrew.net.au/lm-sensors</a>
1884	Sorry, it only contains messages since October 28, 2001.
1885
1886	<p><hr>
1887	Node:<a name="Section%206.6">Section 6.6</a>,
1888	Next:<a rel=next accesskey=n href="#Section%206.7">Section 6.7</a>,
1889	Previous:<a rel=previous accesskey=p href="#Section%206.5">Section 6.5</a>,
1890	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1891	<br>
1892
1893	<h3>6.6 How to submit a patch</h3>
1894
1895	<p>Check out the latest from CVS, then copy the directory to another
1896	directory, and make your changes. Generate the diff with
1897	<code>diff -u2 -r DIR1 DIR2</code>. Or you can generate the diff in CVS with
1898	<code>cvs diff -u2</code>. Send us the patch in an email and tell us what it does.
1899
1900	<p><hr>
1901	Node:<a name="Section%206.7">Section 6.7</a>,
1902	Next:<a rel=next accesskey=n href="#Section%206.8">Section 6.8</a>,
1903	Previous:<a rel=previous accesskey=p href="#Section%206.6">Section 6.6</a>,
1904	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1905	<br>
1906
1907	<h3>6.7 How to REALLY help</h3>
1908
1909	<p>Believe it or not, what we really need help with are:
1910	<ul>
1911	<li>Answering email
1912	<li>Answering support tickets
1913	<li>Submitting patches to Linus, etc.
1914	<li>Creating a sensors.conf database
1915	<li>Creating RPM's
1916	</ul>
1917
1918	<p>Send us email <a href="mailto:sensors@stimpy.netroedge.com">sensors@stimpy.netroedge.com</a> if you can help.
1919	No experience necessary :)
1920
1921	<p><hr>
1922	Node:<a name="Section%206.8">Section 6.8</a>,
1923	Next:<a rel=next accesskey=n href="#Section%206.9">Section 6.9</a>,
1924	Previous:<a rel=previous accesskey=p href="#Section%206.7">Section 6.7</a>,
1925	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1926	<br>
1927
1928	<h3>6.8 How to get release announcements</h3>
1929
1930	<p>We don't have a separate release announcement mailing list;
1931	however, we put all our releases on freshmeat: <a href="http://freshmeat.net">http://freshmeat.net</a>
1932	and you can register on our freshmeat project page <a href="http://freshmeat.net/projects/lm_sensors">http://freshmeat.net/projects/lm_sensors</a>
1933	to 'subscribe to new releases' and then freshmeat
1934	will email you announcement.
1935
1936	<p><hr>
1937	Node:<a name="Section%206.9">Section 6.9</a>,
1938	Previous:<a rel=previous accesskey=p href="#Section%206.8">Section 6.8</a>,
1939	Up:<a rel=up accesskey=u href="#Contribute">Contribute</a>
1940	<br>
1941
1942	<h3>6.9 How to block spam on the project mailing list</h3>
1943
1944	<p>Sorry, we know the spam is a hassle. It would be nice to have a
1945	moderator who can screen everything, but that takes too much time and
1946	delays emails. Right now there is a procmail script which tags likely
1947	spam and puts in a X-SBClass: header. If it is followed by 'Spam', then
1948	it is almost certainly spam, if it is followed by 'Blocked', then it
1949	scores high as being potential spam. You should be able to set some
1950	rules in your mail client to throw those emails into a seperate folder.
1951	It's not bullet proof (some legit mails get tagged wrong, and vice
1952	versa), but it seems to be about 95% accurate in our experience.
1953
1954	<p><hr>
1955	Node:<a name="Version%201%20Specifics">Version 1 Specifics</a>,
1956	Next:<a rel=next accesskey=n href="#Document%20Revisions">Document Revisions</a>,
1957	Previous:<a rel=previous accesskey=p href="#Contribute">Contribute</a>,
1958	Up:<a rel=up accesskey=u href="#Top">Top</a>
1959	<br>
1960
1961	<h2>7 Version 1 Specific Questions</h2>
1962
1963	<ul>
1964	<li><a accesskey=1 href="#Section%207.1">Section 7.1</a>: My mainboard has an SMBus, your code can't find it. Why?
1965	<li><a accesskey=2 href="#Section%207.2">Section 7.2</a>: The modules won't load, saying 'SMBus not detected'.
1966	<li><a accesskey=3 href="#Section%207.3">Section 7.3</a>: I get a "No sensor data yet (try again in a few moments)" msg.
1967	<li><a accesskey=4 href="#Section%207.4">Section 7.4</a>: On my Dell, a LM80 is detected, but all readings are 0!
1968	</ul>
1969
1970	<p>Note: Version 1 is very very old and is not recommended.
1971
1972	<p><hr>
1973	Node:<a name="Section%207.1">Section 7.1</a>,
1974	Next:<a rel=next accesskey=n href="#Section%207.2">Section 7.2</a>,
1975	Up:<a rel=up accesskey=u href="#Version%201%20Specifics">Version 1 Specifics</a>
1976	<br>
1977
1978	<h3>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>
1979
1980	<p>Currently, our code only assumes that an SMBus exists if it originates
1981	from the Intel PIIX4 (82371AB). If your computer doesn't have one, or if your
1982	SMBus originates from a different SMBus 'host', then you are out of luck. :'(
1983	Our experience is, though, that most machines have a PIIX4, and that it is
1984	where the SMBus is hosted.
1985
1986	<p>Regarding the VIA chip set(s):
1987
1988	<p>Right now, the SMBus code depends on the Intel PIIX4 chip to handle
1989	SMBus transactions. The VIA chip set is NOT supported at this time because
1990	it forces much of the SMBus protocol to be implemented by software.
1991
1992	<p>To implement the SMBus correctly with the VIA chip, it needs to be
1993	written at a low level to be quick. A more attractive alternative is to
1994	use the Bios SMBus interface (not always available nor standard).
1995
1996	<p>Version 2 supports the VIA chipset, and will support other chipsets.
1997	Version 1 never will.
1998
1999	<p><hr>
2000	Node:<a name="Section%207.2">Section 7.2</a>,
2001	Next:<a rel=next accesskey=n href="#Section%207.3">Section 7.3</a>,
2002	Previous:<a rel=previous accesskey=p href="#Section%207.1">Section 7.1</a>,
2003	Up:<a rel=up accesskey=u href="#Version%201%20Specifics">Version 1 Specifics</a>
2004	<br>
2005
2006	<h3>7.2 The modules won't load, saying 'SMBus not detected'.</h3>
2007
2008	<p>This should no longer be an issue in 1.4.10 and later; it will
2009	continue loading, but it won't support SMBus-connected devices, of course.
2010
2011	<p><hr>
2012	Node:<a name="Section%207.3">Section 7.3</a>,
2013	Next:<a rel=next accesskey=n href="#Section%207.4">Section 7.4</a>,
2014	Previous:<a rel=previous accesskey=p href="#Section%207.2">Section 7.2</a>,
2015	Up:<a rel=up accesskey=u href="#Version%201%20Specifics">Version 1 Specifics</a>
2016	<br>
2017
2018	<h3>7.3 I try to read <code>/proc/sensors</code>, and I get a "No sensor data yet (try again in a few moments)" message. Why?</h3>
2019
2020	<p>It takes about 1.5 seconds for the LM78 to update all its sensor
2021	values. If we would try to read it before it finished that, you would get
2022	old garbage instead. So you have to wait 1.5 seconds after the module is
2023	inserted before you can access <code>/proc/sensors</code>.
2024
2025	<p>Module versions 1.3.7 and later let the process sleep if it tries
2026	to access sensor data right after insertion time, and do not display this
2027	message anymore.
2028
2029	<p><hr>
2030	Node:<a name="Section%207.4">Section 7.4</a>,
2031	Previous:<a rel=previous accesskey=p href="#Section%207.3">Section 7.3</a>,
2032	Up:<a rel=up accesskey=u href="#Version%201%20Specifics">Version 1 Specifics</a>
2033	<br>
2034
2035	<h3>7.4 On my Dell, a LM80 is detected, but all readings are 0!</h3>
2036
2037	<p>This is a bug we have only observed on Dell computers. There is
2038	probably a problem with the way the SMBus is accessed; but it is not yet
2039	clear whether the problem is in our code or with the Dells.
2040
2041	<p>There are very probably no sensor chips at all on your computer;
2042	but until somebody contacts Dell about this and tells us the results, we
2043	can not be sure.
2044
2045	<p><hr>
2046	Node:<a name="Document%20Revisions">Document Revisions</a>,
2047	Previous:<a rel=previous accesskey=p href="#Version%201%20Specifics">Version 1 Specifics</a>,
2048	Up:<a rel=up accesskey=u href="#Top">Top</a>
2049	<br>
2050
2051	<h2>Appendix A Revision History of This Document</h2>
2052
2053	<ul>
2054	<li>Rev 2.9 (CP) Converted to Gnu texinfo format, 20020910
2055	<li>Rev 2.8 (MDS) Minor updates 20020710, released with lm_sensors 2.6.4
2056	<li>Rev 2.7 (MDS) Minor updates 20020425
2057	<li>Rev 2.6 (MDS) Minor updates 20020115, released with lm_sensors 2.6.3
2058	<li>Rev 2.5 (MDS) Minor updates 20011111, released with lm_sensors 2.6.2
2059	<li>Rev 2.4 (MDS) Minor updates 20010722
2060	<li>Rev 2.3 (MDS) General update, 20010224, released with lm_sensors 2.6.0.
2061	<li>Rev 2.2 (Frodo) Corrections for lm_sensors 2.4, 19990920
2062	<li>Rev 2.1 (Frodo) Corrections for lm_sensors 2.2, 19990112
2063	<li>Rev 2.0 (Frodo) Major revision for lm_sensors 2.1, 19981229
2064	<li>Rev 1.10 (Frodo) Modified 3.8, updated some other things, 19980924
2065	<li>Rev 1.9 (Frodo) Added 3.15, 19980906
2066	<li>Rev 1.8 (Frodo) Added 3.14, 19980905
2067	<li>Rev 1.7 (Phil) Added 3.13 and some other minor changes, 19980901
2068	<li>Rev 1.6 (Frodo) Added 4, 4.1, 4.2, 4.3, 4.4, 4.5, 19980901
2069	<li>Rev 1.5 (Frodo) Added 2.3, 2.4, 3.9, 3.10, 3.11, 19980826
2070	<li>Rev 1.4 (Frodo) Added some more Winbond information, and 3.5-3.8, 19980817
2071	<li>Rev 1.3 Added info on the Winbond chip, 19980816
2072	<li>Rev 1.2 Adapation by Frodo Looijaard, 19980810
2073	<li>Rev 1.1 Modifications by Philip Edelbrock, 19980809
2074	<li>Rev 1.0 Written by Philip Edelbrock, 19980803
2075	</ul>
2076
2077	</body></html>

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