39 строки
1.3 KiB
ReStructuredText
39 строки
1.3 KiB
ReStructuredText
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Kernel driver ds620
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===================
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Supported chips:
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* Dallas Semiconductor DS620
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Prefix: 'ds620'
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Datasheet: Publicly available at the Dallas Semiconductor website
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http://www.dalsemi.com/
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Authors:
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Roland Stigge <stigge@antcom.de>
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based on ds1621.c by
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Christian W. Zuckschwerdt <zany@triq.net>
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Description
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-----------
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The DS620 is a (one instance) digital thermometer and thermostat. It has both
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high and low temperature limits which can be user defined (i.e. programmed
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into non-volatile on-chip registers). Temperature range is -55 degree Celsius
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to +125. Between 0 and 70 degree Celsius, accuracy is 0.5 Kelvin. The value
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returned via sysfs displays post decimal positions.
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The thermostat function works as follows: When configured via platform_data
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(struct ds620_platform_data) .pomode == 0 (default), the thermostat output pin
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PO is always low. If .pomode == 1, the thermostat is in PO_LOW mode. I.e., the
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output pin PO becomes active when the temperature falls below temp1_min and
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stays active until the temperature goes above temp1_max.
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Likewise, with .pomode == 2, the thermostat is in PO_HIGH mode. I.e., the PO
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output pin becomes active when the temperature goes above temp1_max and stays
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active until the temperature falls below temp1_min.
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The PO output pin of the DS620 operates active-low.
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