NCT(4)

NAME
nct - Nuvoton NCT5104D SuperIO driver

SYNOPSIS
nct0 at isa? port ?
nct0 at isa? port 0x2e
nct0 at isa? port 0x4e
gpio* at nct?

DESCRIPTION
The nct driver supports the GPIO functions of the NCT5104D. The driver does not support the watchdog function of the chip. The chip's UARTs are driven by the com(4) driver.

The probe routine for this device is invasive. The chip will be probed for only if the device is configured into the kernel with a fixed port number (0x2e or 0x4e), or if running on a system that is known to have a NCT5104D, such as the PC Engines APU line of systems.

GPIO pins on this chip are shared with the 3rd UART, 4th UART, a clock input line, and the watchdog timer. If any these functions have been enabled by the BIOS, the nct driver will not take control of the corresponding GPIO lines. At attach time, the driver logs which of the 17 GPIO lines are enabled.

SEE ALSO
gpio(4), isa(4), gpioctl(8)

HISTORY
The nct driver first appeared in NetBSD 10.

CAVEATS
If the chip has not been configured in a complete and accurate manner by the BIOS, GPIO lines may be needlessly disabled.