GPIOOW(4)

GPIOOW(4) | Device Drivers Manual | GPIOOW(4)

# NAME

`gpioow` —
1-Wire bus bit-banging through GPIO pin

# SYNOPSIS

`gpioow* at gpio? offset 0 mask 0x1`
`gpioow* at gpio?`
`onewire* at gpioow?`

# DESCRIPTION

The `gpioow` driver allows bit-banging a 1-Wire bus as a master using one GPIO pin. The pin is used as a data signal. The GPIO pin must be able to drive an output and read an input.

The pin number is specified in the kernel configuration with the offset locator. The mask locator should always be 0x1. The offset and mask can also be specified when `gpioow` is attached at runtime using the `GPIOATTACH` ioctl(2) on the gpio(4) device.

# SEE ALSO

gpio(4), intro(4), onewire(4)

# HISTORY

The `gpioow` driver first appeared in OpenBSD 4.0 and NetBSD 4.0.

# AUTHORS

The `gpioow` driver was written by Alexander Yurchenko <grange@openbsd.org> and was ported to NetBSD by Jeff Rizzo <riz@NetBSD.org>.

July 19, 2009 | NetBSD 9.3