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SCHSIO(4) Device Drivers Manual SCHSIO(4)

schsioSMSC SCH311x LPC Super I/O

schsio* at isa? port 0x2e flags 0x0000
schsio* at isa? port 0x4e flags 0x0000
schsio* at isa? port 0x162e flags 0x0000
schsio* at isa? port 0x164e flags 0x0000

The schsio driver provides support for the SMSC SCH3112, SCH3114, and SCH3116 ICs. Among other things, the devices contain environment sensors, a watchdog timer, and fan control. The schsio driver supports the environment sensors and the watchdog timer.

The hardware provides the following sensors:

uK IC internal thermal diode
uK External thermal diode
uK External thermal diode
RPM Fan tachometer
RPM Fan tachometer
RPM Fan tachometer
uV Voltage
uV Voltage
uV Voltage
uV Voltage
uV Voltage
uV Voltage
uV Voltage

schsio provides the standard watchdog(4) interface and may be used with watchdogd(8). The watchdog timer may be configured to a value from 1 second to 255 minutes. The watchdog timer has a resolution of 1 second in the timeout interval 1 to 255 seconds. Outside this interval, the resolution is 1 minute.

Note that the pin used for signalling the timer expiration is configurable and may on some boards be intended for other uses than this. Because of this, the chip may not by default be configured to use the pin for watchdog operation. To force the schsio device to use the pin for watchdog operation, the driver may be configured with an autoconf(9) flags setting of 0x0001.

intro(4), isa(4), watchdog(4), sensorsd(8), sysctl(8), watchdogd(8), autoconf(9)

The schsio driver first appeared in OpenBSD 4.5.

The schsio driver was written by Michael Knudsen <mk@openbsd.org>.

July 16, 2013 OpenBSD-5.9