SCHSIO(4)

Bestie, you're reading SCHSIO(4) from the Kernel Interfaces Manual — the SMSC SCH311x LPC Super I/O page, and it's giving hardware-realness 💅✨

✨ NAME ✨

schsio — SMSC SCH311x LPC Super I/O. Iconic. 💖

🌸 SYNOPSIS 🌸

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

💖 DESCRIPTION 💖

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. Slay, but make it sensors. 🌡️

The hardware provides the following sensors:

• Internal diode — units uK; typical use: IC internal thermal diode
• Remote diode 1 — units uK; typical use: External thermal diode
• Remove diode 2 — units uK; typical use: External thermal diode
• FAN1 — units RPM; typical use: Fan tachometer
• FAN2 — units RPM; typical use: Fan tachometer
• FAN3 — units RPM; typical use: Fan tachometer
• +2.5V — units uV; typical use: Voltage
• +1.5V (Vccp) — units uV; typical use: Voltage
• +3.3V (VCC) — units uV; typical use: Voltage
• +5V — units uV; typical use: Voltage
• +12V — units uV; typical use: Voltage
• +3.3V (VTR) — units uV; typical use: Voltage
• +3V (Vbat) — units uV; typical use: 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. 💀

🦋 SEE ALSO 🦋

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

🎀 HISTORY 🎀

The schsio driver first appeared in OpenBSD 4.5. Vintage but still cute. 🫶

👑 AUTHORS 👑

The schsio driver was written by Michael Knudsen <mk@openbsd.org>. Respect the icon who wrote it. 💌

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Signing off with Debian as the source/version, July 16, 2013 as the date, and SCHSIO(4) as the page — mwah 💋🫶