DS2482OW(4) | Device Drivers Manual | DS2482OW(4)

# NAME

`ds2482ow` — Driver for Maxim DS2482-100 and DS2482-800 IC2 to 1-Wire bridge

# SYNOPSIS

`ds2482ow* at iic? addr 0x18`
`ds2482ow* at iic? addr 0x19`
`ds2482ow* at iic? addr 0x1a`
`ds2482ow* at iic? addr 0x1b`
`ds2482ow* at iic? addr 0x1c DS2482-800 only`
`ds2482ow* at iic? addr 0x1d DS2482-800 only`
`ds2482ow* at iic? addr 0x1e DS2482-800 only`
`ds2482ow* at iic? addr 0x1f DS2482-800 only`
`onewire* at ds2482ow?`

# DESCRIPTION

The `ds2482ow` driver provides 1 or 8 onewire(4) busses via an I2C interface. The `ds2482ow` addr argument selects the address at the iic(4) bus. The chip generates all of the needed 1-Wire pulses on its own and provides for the pullup needed on the 1-Wire data line. The method that the chip uses for pullup can be changed through sysctl(8) nodes.

# SYSCTL VARIABLES

The following sysctl(3) variables are provided:

`hw.ds2482ow0.pullup.active`
  If true, turn on active pullup on all channels supported by the chip.
`hw.ds2482ow0.pullup.strong`
  If true, turn on strong pullup on all channels that the chip supports and on the DS2482-100 chip, allow the PCTLZ pin to provide addition current to the 1-Wire bus. This mode conflicts with a 1-Wire reset and will be disabled if that command is sent to the 1-Wire bus.

`If neither active pullup or strong pullup are enabled the chip will`
  use an internal passive resister.
`hw.ds2482ow0.debug`
  If the driver is compiled with `DS2482_DEBUG`, this node will appear and can be used to set the debugging level.

# SEE ALSO

onewire(4), iic(4), sysctl(8)

# HISTORY

The `ds2482ow` driver first appeared in NetBSD 11.0.

# AUTHORS

The `ds2482ow` driver was written by Brad Spencer <brad@anduin.eldar.org>.

# BUGS

The DS2482 chip supports overdrive speed on a 1-Wire bus. This driver does not support overdrive speed mode.

October 31, 2024 | NetBSD 11.0