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diff --git a/Documentation/i2c/chips/lm83 b/Documentation/i2c/chips/lm83 deleted file mode 100644 index 061d9ed8ff43..000000000000 --- a/Documentation/i2c/chips/lm83 +++ /dev/null @@ -1,76 +0,0 @@ -Kernel driver lm83 -================== - -Supported chips: - * National Semiconductor LM83 - Prefix: 'lm83' - Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e - Datasheet: Publicly available at the National Semiconductor website - http://www.national.com/pf/LM/LM83.html - - -Author: Jean Delvare <khali@linux-fr.org> - -Description ------------ - -The LM83 is a digital temperature sensor. It senses its own temperature as -well as the temperature of up to three external diodes. It is compatible -with many other devices such as the LM84 and all other ADM1021 clones. -The main difference between the LM83 and the LM84 in that the later can -only sense the temperature of one external diode. - -Using the adm1021 driver for a LM83 should work, but only two temperatures -will be reported instead of four. - -The LM83 is only found on a handful of motherboards. Both a confirmed -list and an unconfirmed list follow. If you can confirm or infirm the -fact that any of these motherboards do actually have an LM83, please -contact us. Note that the LM90 can easily be misdetected as a LM83. - -Confirmed motherboards: - SBS P014 - -Unconfirmed motherboards: - Gigabyte GA-8IK1100 - Iwill MPX2 - Soltek SL-75DRV5 - -The driver has been successfully tested by Magnus Forsström, who I'd -like to thank here. More testers will be of course welcome. - -The fact that the LM83 is only scarcely used can be easily explained. -Most motherboards come with more than just temperature sensors for -health monitoring. They also have voltage and fan rotation speed -sensors. This means that temperature-only chips are usually used as -secondary chips coupled with another chip such as an IT8705F or similar -chip, which provides more features. Since systems usually need three -temperature sensors (motherboard, processor, power supply) and primary -chips provide some temperature sensors, the secondary chip, if needed, -won't have to handle more than two temperatures. Thus, ADM1021 clones -are sufficient, and there is no need for a four temperatures sensor -chip such as the LM83. The only case where using an LM83 would make -sense is on SMP systems, such as the above-mentioned Iwill MPX2, -because you want an additional temperature sensor for each additional -CPU. - -On the SBS P014, this is different, since the LM83 is the only hardware -monitoring chipset. One temperature sensor is used for the motherboard -(actually measuring the LM83's own temperature), one is used for the -CPU. The two other sensors must be used to measure the temperature of -two other points of the motherboard. We suspect these points to be the -north and south bridges, but this couldn't be confirmed. - -All temperature values are given in degrees Celsius. Local temperature -is given within a range of 0 to +85 degrees. Remote temperatures are -given within a range of 0 to +125 degrees. Resolution is 1.0 degree, -accuracy is guaranteed to 3.0 degrees (see the datasheet for more -details). - -Each sensor has its own high limit, but the critical limit is common to -all four sensors. There is no hysteresis mechanism as found on most -recent temperature sensors. - -The lm83 driver will not update its values more frequently than every -other second; reading them more often will do no harm, but will return -'old' values. |
