| Kernel driver lm75 |
| ================== |
| |
| Supported chips: |
| * National Semiconductor LM75 |
| Prefix: 'lm75' |
| Addresses scanned: I2C 0x48 - 0x4f |
| Datasheet: Publicly available at the National Semiconductor website |
| http://www.national.com/ |
| * Dallas Semiconductor DS75 |
| Prefix: 'lm75' |
| Addresses scanned: I2C 0x48 - 0x4f |
| Datasheet: Publicly available at the Dallas Semiconductor website |
| http://www.maxim-ic.com/ |
| * Dallas Semiconductor DS1775 |
| Prefix: 'lm75' |
| Addresses scanned: I2C 0x48 - 0x4f |
| Datasheet: Publicly available at the Dallas Semiconductor website |
| http://www.maxim-ic.com/ |
| * Maxim MAX6625, MAX6626 |
| Prefix: 'lm75' |
| Addresses scanned: I2C 0x48 - 0x4b |
| Datasheet: Publicly available at the Maxim website |
| http://www.maxim-ic.com/ |
| * Microchip (TelCom) TCN75 |
| Prefix: 'lm75' |
| Addresses scanned: I2C 0x48 - 0x4f |
| Datasheet: Publicly available at the Microchip website |
| http://www.microchip.com/ |
| |
| Author: Frodo Looijaard <frodol@dds.nl> |
| |
| Description |
| ----------- |
| |
| The LM75 implements one temperature sensor. Limits can be set through the |
| Overtemperature Shutdown register and Hysteresis register. Each value can be |
| set and read to half-degree accuracy. |
| An alarm is issued (usually to a connected LM78) when the temperature |
| gets higher then the Overtemperature Shutdown value; it stays on until |
| the temperature falls below the Hysteresis value. |
| All temperatures are in degrees Celsius, and are guaranteed within a |
| range of -55 to +125 degrees. |
| |
| The LM75 only updates its values each 1.5 seconds; reading it more often |
| will do no harm, but will return 'old' values. |
| |
| The LM75 is usually used in combination with LM78-like chips, to measure |
| the temperature of the processor(s). |
| |
| The DS75, DS1775, MAX6625, and MAX6626 are supported as well. |
| They are not distinguished from an LM75. While most of these chips |
| have three additional bits of accuracy (12 vs. 9 for the LM75), |
| the additional bits are not supported. Not only that, but these chips will |
| not be detected if not in 9-bit precision mode (use the force parameter if |
| needed). |
| |
| The TCN75 is supported as well, and is not distinguished from an LM75. |
| |
| The LM75 is essentially an industry standard; there may be other |
| LM75 clones not listed here, with or without various enhancements, |
| that are supported. |
| |
| The LM77 is not supported, contrary to what we pretended for a long time. |
| Both chips are simply not compatible, value encoding differs. |
