17ebd8b66SMauro Carvalho ChehabKernel driver lm83 27ebd8b66SMauro Carvalho Chehab================== 37ebd8b66SMauro Carvalho Chehab 47ebd8b66SMauro Carvalho ChehabSupported chips: 57ebd8b66SMauro Carvalho Chehab 67ebd8b66SMauro Carvalho Chehab * National Semiconductor LM83 77ebd8b66SMauro Carvalho Chehab 87ebd8b66SMauro Carvalho Chehab Prefix: 'lm83' 97ebd8b66SMauro Carvalho Chehab 107ebd8b66SMauro Carvalho Chehab Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e 117ebd8b66SMauro Carvalho Chehab 127ebd8b66SMauro Carvalho Chehab Datasheet: Publicly available at the National Semiconductor website 137ebd8b66SMauro Carvalho Chehab 147ebd8b66SMauro Carvalho Chehab http://www.national.com/pf/LM/LM83.html 157ebd8b66SMauro Carvalho Chehab 167ebd8b66SMauro Carvalho Chehab * National Semiconductor LM82 177ebd8b66SMauro Carvalho Chehab 187ebd8b66SMauro Carvalho Chehab Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e 197ebd8b66SMauro Carvalho Chehab 207ebd8b66SMauro Carvalho Chehab Datasheet: Publicly available at the National Semiconductor website 217ebd8b66SMauro Carvalho Chehab 227ebd8b66SMauro Carvalho Chehab http://www.national.com/pf/LM/LM82.html 237ebd8b66SMauro Carvalho Chehab 247ebd8b66SMauro Carvalho ChehabAuthor: Jean Delvare <jdelvare@suse.de> 257ebd8b66SMauro Carvalho Chehab 267ebd8b66SMauro Carvalho ChehabDescription 277ebd8b66SMauro Carvalho Chehab----------- 287ebd8b66SMauro Carvalho Chehab 297ebd8b66SMauro Carvalho ChehabThe LM83 is a digital temperature sensor. It senses its own temperature as 307ebd8b66SMauro Carvalho Chehabwell as the temperature of up to three external diodes. The LM82 is 317ebd8b66SMauro Carvalho Chehaba stripped down version of the LM83 that only supports one external diode. 327ebd8b66SMauro Carvalho ChehabBoth are compatible with many other devices such as the LM84 and all 337ebd8b66SMauro Carvalho Chehabother ADM1021 clones. The main difference between the LM83 and the LM84 347ebd8b66SMauro Carvalho Chehabin that the later can only sense the temperature of one external diode. 357ebd8b66SMauro Carvalho Chehab 367ebd8b66SMauro Carvalho ChehabUsing the adm1021 driver for a LM83 should work, but only two temperatures 377ebd8b66SMauro Carvalho Chehabwill be reported instead of four. 387ebd8b66SMauro Carvalho Chehab 397ebd8b66SMauro Carvalho ChehabThe LM83 is only found on a handful of motherboards. Both a confirmed 407ebd8b66SMauro Carvalho Chehablist and an unconfirmed list follow. If you can confirm or infirm the 417ebd8b66SMauro Carvalho Chehabfact that any of these motherboards do actually have an LM83, please 427ebd8b66SMauro Carvalho Chehabcontact us. Note that the LM90 can easily be misdetected as a LM83. 437ebd8b66SMauro Carvalho Chehab 447ebd8b66SMauro Carvalho ChehabConfirmed motherboards: 457ebd8b66SMauro Carvalho Chehab === ===== 467ebd8b66SMauro Carvalho Chehab SBS P014 477ebd8b66SMauro Carvalho Chehab SBS PSL09 487ebd8b66SMauro Carvalho Chehab === ===== 497ebd8b66SMauro Carvalho Chehab 507ebd8b66SMauro Carvalho ChehabUnconfirmed motherboards: 517ebd8b66SMauro Carvalho Chehab =========== ========== 527ebd8b66SMauro Carvalho Chehab Gigabyte GA-8IK1100 537ebd8b66SMauro Carvalho Chehab Iwill MPX2 547ebd8b66SMauro Carvalho Chehab Soltek SL-75DRV5 557ebd8b66SMauro Carvalho Chehab =========== ========== 567ebd8b66SMauro Carvalho Chehab 577ebd8b66SMauro Carvalho ChehabThe LM82 is confirmed to have been found on most AMD Geode reference 587ebd8b66SMauro Carvalho Chehabdesigns and test platforms. 597ebd8b66SMauro Carvalho Chehab 607ebd8b66SMauro Carvalho ChehabThe driver has been successfully tested by Magnus Forsström, who I'd 617ebd8b66SMauro Carvalho Chehablike to thank here. More testers will be of course welcome. 627ebd8b66SMauro Carvalho Chehab 637ebd8b66SMauro Carvalho ChehabThe fact that the LM83 is only scarcely used can be easily explained. 647ebd8b66SMauro Carvalho ChehabMost motherboards come with more than just temperature sensors for 657ebd8b66SMauro Carvalho Chehabhealth monitoring. They also have voltage and fan rotation speed 667ebd8b66SMauro Carvalho Chehabsensors. This means that temperature-only chips are usually used as 677ebd8b66SMauro Carvalho Chehabsecondary chips coupled with another chip such as an IT8705F or similar 687ebd8b66SMauro Carvalho Chehabchip, which provides more features. Since systems usually need three 697ebd8b66SMauro Carvalho Chehabtemperature sensors (motherboard, processor, power supply) and primary 707ebd8b66SMauro Carvalho Chehabchips provide some temperature sensors, the secondary chip, if needed, 717ebd8b66SMauro Carvalho Chehabwon't have to handle more than two temperatures. Thus, ADM1021 clones 727ebd8b66SMauro Carvalho Chehabare sufficient, and there is no need for a four temperatures sensor 737ebd8b66SMauro Carvalho Chehabchip such as the LM83. The only case where using an LM83 would make 747ebd8b66SMauro Carvalho Chehabsense is on SMP systems, such as the above-mentioned Iwill MPX2, 757ebd8b66SMauro Carvalho Chehabbecause you want an additional temperature sensor for each additional 767ebd8b66SMauro Carvalho ChehabCPU. 777ebd8b66SMauro Carvalho Chehab 787ebd8b66SMauro Carvalho ChehabOn the SBS P014, this is different, since the LM83 is the only hardware 797ebd8b66SMauro Carvalho Chehabmonitoring chipset. One temperature sensor is used for the motherboard 807ebd8b66SMauro Carvalho Chehab(actually measuring the LM83's own temperature), one is used for the 817ebd8b66SMauro Carvalho ChehabCPU. The two other sensors must be used to measure the temperature of 827ebd8b66SMauro Carvalho Chehabtwo other points of the motherboard. We suspect these points to be the 837ebd8b66SMauro Carvalho Chehabnorth and south bridges, but this couldn't be confirmed. 847ebd8b66SMauro Carvalho Chehab 857ebd8b66SMauro Carvalho ChehabAll temperature values are given in degrees Celsius. Local temperature 867ebd8b66SMauro Carvalho Chehabis given within a range of 0 to +85 degrees. Remote temperatures are 877ebd8b66SMauro Carvalho Chehabgiven within a range of 0 to +125 degrees. Resolution is 1.0 degree, 887ebd8b66SMauro Carvalho Chehabaccuracy is guaranteed to 3.0 degrees (see the datasheet for more 897ebd8b66SMauro Carvalho Chehabdetails). 907ebd8b66SMauro Carvalho Chehab 917ebd8b66SMauro Carvalho ChehabEach sensor has its own high limit, but the critical limit is common to 927ebd8b66SMauro Carvalho Chehaball four sensors. There is no hysteresis mechanism as found on most 937ebd8b66SMauro Carvalho Chehabrecent temperature sensors. 947ebd8b66SMauro Carvalho Chehab 957ebd8b66SMauro Carvalho ChehabThe lm83 driver will not update its values more frequently than every 967ebd8b66SMauro Carvalho Chehabother second; reading them more often will do no harm, but will return 977ebd8b66SMauro Carvalho Chehab'old' values. 98