4 First of all, what I know about uGuru is no fact based on any help, hints or
5 datasheet from Abit. The data I have got on uGuru have I assembled through
6 my weak knowledge in "backwards engineering".
7 And just for the record, you may have noticed uGuru isn't a chip developed by
8 Abit, as they claim it to be. It's realy just an microprocessor (uC) created by
9 Winbond (W83L950D). And no, reading the manual for this specific uC or
10 mailing Windbond for help won't give any usefull data about uGuru, as it is
11 the program inside the uC that is responding to calls.
13 Olle Sandberg <ollebull@gmail.com>, 2005-05-25
16 Original version by Olle Sandberg who did the heavy lifting of the initial
17 reverse engineering. This version has been almost fully rewritten for clarity
18 and extended with write support and info on more databanks, the write support
19 is once again reverse engineered by Olle the additional databanks have been
20 reverse engineered by me. I would like to express my thanks to Olle, this
21 document and the Linux driver could not have been written without his efforts.
23 Note: because of the lack of specs only the sensors part of the uGuru is
24 described here and not the CPU / RAM / etc voltage & frequency control.
26 Hans de Goede <j.w.r.degoede@hhs.nl>, 28-01-2006
32 As far as known the uGuru is always placed at and using the (ISA) I/O-ports
33 0xE0 and 0xE4, so we don't have to scan any port-range, just check what the two
34 ports are holding for detection. We will refer to 0xE0 as CMD (command-port)
35 and 0xE4 as DATA because Abit refers to them with these names.
37 If DATA holds 0x00 or 0x08 and CMD holds 0x00 or 0xAC an uGuru could be
38 present. We have to check for two different values at data-port, because
39 after a reboot uGuru will hold 0x00 here, but if the driver is removed and
40 later on attached again data-port will hold 0x08, more about this later.
42 After wider testing of the Linux kernel driver some variants of the uGuru have
43 turned up which will hold 0x00 instead of 0xAC at the CMD port, thus we also
44 have to test CMD for two different values. On these uGuru's DATA will initally
45 hold 0x09 and will only hold 0x08 after reading CMD first, so CMD must be read
48 To be really sure an uGuru is present a test read of one or more register
58 The uGuru has a number of different addressing levels. The first addressing
59 level we will call banks. A bank holds data for one or more sensors. The data
60 in a bank for a sensor is one or more bytes large.
62 The number of bytes is fixed for a given bank, you should always read or write
63 that many bytes, reading / writing more will fail, the results when writing
64 less then the number of bytes for a given bank are undetermined.
66 See below for all known bank addresses, numbers of sensors in that bank,
67 number of bytes data per sensor and contents/meaning of those bytes.
69 Although both this document and the kernel driver have kept the sensor
70 terminoligy for the addressing within a bank this is not 100% correct, in
71 bank 0x24 for example the addressing within the bank selects a PWM output not
74 Notice that some banks have both a read and a write address this is how the
75 uGuru determines if a read from or a write to the bank is taking place, thus
76 when reading you should always use the read address and when writing the
77 write address. The write address is always one (1) more then the read address.
83 Before you can read from or write to the uGuru you must first put the uGuru
86 To put the uGuru in ready mode first write 0x00 to DATA and then wait for DATA
87 to hold 0x09, DATA should read 0x09 within 250 read cycles.
89 Next CMD _must_ be read and should hold 0xAC, usually CMD will hold 0xAC the
90 first read but sometimes it takes a while before CMD holds 0xAC and thus it
91 has to be read a number of times (max 50).
93 After reading CMD, DATA should hold 0x08 which means that the uGuru is ready
94 for input. As above DATA will usually hold 0x08 the first read but not always.
95 This step can be skipped, but it is undetermined what happens if the uGuru has
96 not yet reported 0x08 at DATA and you proceed with writing a bank address.
99 Sending bank and sensor addresses to the uGuru
100 ----------------------------------------------
102 First the uGuru must be in "ready" mode as described above, DATA should hold
103 0x08 indicating that the uGuru wants input, in this case the bank address.
105 Next write the bank address to DATA. After the bank address has been written
106 wait for to DATA to hold 0x08 again indicating that it wants / is ready for
107 more input (max 250 reads).
109 Once DATA holds 0x08 again write the sensor address to CMD.
115 First send the bank and sensor addresses as described above.
116 Then for each byte of data you want to read wait for DATA to hold 0x01
117 which indicates that the uGuru is ready to be read (max 250 reads) and once
118 DATA holds 0x01 read the byte from CMD.
120 Once all bytes have been read data will hold 0x09, but there is no reason to
121 test for this. Notice that the number of bytes is bank address dependent see
124 After completing a successfull read it is advised to put the uGuru back in
125 ready mode, so that it is ready for the next read / write cycle. This way
126 if your program / driver is unloaded and later loaded again the detection
127 algorithm described above will still work.
134 First send the bank and sensor addresses as described above.
135 Then for each byte of data you want to write wait for DATA to hold 0x00
136 which indicates that the uGuru is ready to be written (max 250 reads) and
137 once DATA holds 0x00 write the byte to CMD.
139 Once all bytes have been written wait for DATA to hold 0x01 (max 250 reads)
140 don't ask why this is the way it is.
142 Once DATA holds 0x01 read CMD it should hold 0xAC now.
144 After completing a successfull write it is advised to put the uGuru back in
145 ready mode, so that it is ready for the next read / write cycle. This way
146 if your program / driver is unloaded and later loaded again the detection
147 algorithm described above will still work.
153 After wider testing of the Linux kernel driver some variants of the uGuru have
154 turned up which do not hold 0x08 at DATA within 250 reads after writing the
155 bank address. With these versions this happens quite frequent, using larger
156 timeouts doesn't help, they just go offline for a second or 2, doing some
157 internal callibration or whatever. Your code should be prepared to handle
158 this and in case of no response in this specific case just goto sleep for a
159 while and then retry.
167 This bank contains 0 sensors, iow the sensor address is ignored (but must be
168 written) just use 0. Bank 0x20 contains 3 bytes:
171 This byte holds the alarm flags for sensor 0-7 of Sensor Bank1, with bit 0
172 corresponding to sensor 0, 1 to 1, etc.
175 This byte holds the alarm flags for sensor 8-15 of Sensor Bank1, with bit 0
176 corresponding to sensor 8, 1 to 9, etc.
179 This byte holds the alarm flags for sensor 0-5 of Sensor Bank2, with bit 0
180 corresponding to sensor 0, 1 to 1, etc.
183 Bank 0x21 Sensor Bank1 Values / Readings (R)
184 --------------------------------------------
185 This bank contains 16 sensors, for each sensor it contains 1 byte.
186 So far the following sensors are known to be available on all motherboards:
189 Sensor 3 CPU core volt
191 Sensor 10 DDR Vtt volt
195 This byte holds the reading from the sensor. Sensors in Bank1 can be both
196 volt and temp sensors, this is motherboard specific. The uGuru however does
197 seem to know (be programmed with) what kindoff sensor is attached see Sensor
198 Bank1 Settings description.
200 Volt sensors use a linear scale, a reading 0 corresponds with 0 volt and a
201 reading of 255 with 3494 mV. The sensors for higher voltages however are
202 connected through a division circuit. The currently known division circuits
203 in use result in ranges of: 0-4361mV, 0-6248mV or 0-14510mV. 3.3 volt sources
204 use the 0-4361mV range, 5 volt the 0-6248mV and 12 volt the 0-14510mV .
206 Temp sensors also use a linear scale, a reading of 0 corresponds with 0 degree
207 Celsius and a reading of 255 with a reading of 255 degrees Celsius.
210 Bank 0x22 Sensor Bank1 Settings (R)
211 Bank 0x23 Sensor Bank1 Settings (W)
212 -----------------------------------
214 This bank contains 16 sensors, for each sensor it contains 3 bytes. Each
215 set of 3 bytes contains the settings for the sensor with the same sensor
216 address in Bank 0x21 .
219 Alarm behaviour for the selected sensor. A 1 enables the described behaviour.
220 Bit 0: Give an alarm if measured temp is over the warning threshold (RW) *
221 Bit 1: Give an alarm if measured volt is over the max threshold (RW) **
222 Bit 2: Give an alarm if measured volt is under the min threshold (RW) **
223 Bit 3: Beep if alarm (RW)
224 Bit 4: 1 if alarm cause measured temp is over the warning threshold (R)
225 Bit 5: 1 if alarm cause measured volt is over the max threshold (R)
226 Bit 6: 1 if alarm cause measured volt is under the min threshold (R)
227 Bit 7: Volt sensor: Shutdown if alarm persist for more then 4 seconds (RW)
228 Temp sensor: Shutdown if temp is over the shutdown threshold (RW)
230 * This bit is only honored/used by the uGuru if a temp sensor is connected
231 ** This bit is only honored/used by the uGuru if a volt sensor is connected
232 Note with some trickery this can be used to find out what kinda sensor is
233 detected see the Linux kernel driver for an example with many comments on
237 Temp sensor: warning threshold (scale as bank 0x21)
238 Volt sensor: min threshold (scale as bank 0x21)
241 Temp sensor: shutdown threshold (scale as bank 0x21)
242 Volt sensor: max threshold (scale as bank 0x21)
245 Bank 0x24 PWM outputs for FAN's (R)
246 Bank 0x25 PWM outputs for FAN's (W)
247 -----------------------------------
249 This bank contains 3 "sensors", for each sensor it contains 5 bytes.
250 Sensor 0 usually controls the CPU fan
251 Sensor 1 usually controls the NB (or chipset for single chip) fan
252 Sensor 2 usually controls the System fan
255 Flag 0x80 to enable control, Fan runs at 100% when disabled.
256 low nibble (temp)sensor address at bank 0x21 used for control.
259 0-255 = 0-12v (linear), specify voltage at which fan will rotate when under
260 low threshold temp (specified in byte 3)
263 0-255 = 0-12v (linear), specify voltage at which fan will rotate when above
264 high threshold temp (specified in byte 4)
267 Low threshold temp (scale as bank 0x21)
270 High threshold temp (scale as bank 0x21)
273 Bank 0x26 Sensors Bank2 Values / Readings (R)
274 ---------------------------------------------
276 This bank contains 6 sensors (AFAIK), for each sensor it contains 1 byte.
277 So far the following sensors are known to be available on all motherboards:
278 Sensor 0: CPU fan speed
279 Sensor 1: NB (or chipset for single chip) fan speed
280 Sensor 2: SYS fan speed
283 This byte holds the reading from the sensor. 0-255 = 0-15300 (linear)
286 Bank 0x27 Sensors Bank2 Settings (R)
287 Bank 0x28 Sensors Bank2 Settings (W)
288 ------------------------------------
290 This bank contains 6 sensors (AFAIK), for each sensor it contains 2 bytes.
293 Alarm behaviour for the selected sensor. A 1 enables the described behaviour.
294 Bit 0: Give an alarm if measured rpm is under the min threshold (RW)
295 Bit 3: Beep if alarm (RW)
296 Bit 7: Shutdown if alarm persist for more then 4 seconds (RW)
299 min threshold (scale as bank 0x26)
302 Warning for the adventerous
303 ===========================
305 A word of caution to those who want to experiment and see if they can figure
306 the voltage / clock programming out, I tried reading and only reading banks
307 0-0x30 with the reading code used for the sensor banks (0x20-0x28) and this
308 resulted in a _permanent_ reprogramming of the voltages, luckily I had the
309 sensors part configured so that it would shutdown my system on any out of spec
310 voltages which proprably safed my computer (after a reboot I managed to
311 immediatly enter the bios and reload the defaults). This probably means that
312 the read/write cycle for the non sensor part is different from the sensor part.