38 lines
1.5 KiB
Plaintext
38 lines
1.5 KiB
Plaintext
Kernel driver lm95245
|
|
==================
|
|
|
|
Supported chips:
|
|
* National Semiconductor LM95245
|
|
Addresses scanned: I2C 0x18, 0x19, 0x29, 0x4c, 0x4d
|
|
Datasheet: Publicly available at the National Semiconductor website
|
|
http://www.national.com/mpf/LM/LM95245.html
|
|
|
|
|
|
Author: Alexander Stein <alexander.stein@systec-electronic.com>
|
|
|
|
Description
|
|
-----------
|
|
|
|
The LM95245 is an 11-bit digital temperature sensor with a 2-wire System
|
|
Management Bus (SMBus) interface and TruTherm technology that can monitor
|
|
the temperature of a remote diode as well as its own temperature.
|
|
The LM95245 can be used to very accurately monitor the temperature of
|
|
external devices such as microprocessors.
|
|
|
|
All temperature values are given in millidegrees Celsius. Local temperature
|
|
is given within a range of -127 to +127.875 degrees. Remote temperatures are
|
|
given within a range of -127 to +255 degrees. Resolution depends on
|
|
temperature input and range.
|
|
|
|
Each sensor has its own critical limit. Additionally, there is a relative
|
|
hysteresis value common to both critical limits. To make life easier to
|
|
user-space applications, two absolute values are exported, one for each
|
|
channel, but these values are of course linked. Only the local hysteresis
|
|
can be set from user-space, and the same delta applies to the remote
|
|
hysteresis.
|
|
|
|
The lm95245 driver can change its update interval to a fixed set of values.
|
|
It will round up to the next selectable interval. See the datasheet for exact
|
|
values. Reading sensor values more often will do no harm, but will return
|
|
'old' values.
|