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