ds2482ow(4) - NetBSD Manual Pages

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DS2482OW(4)             NetBSD Kernel Interfaces 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 inter-
     face.  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 pro-
     vides 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 sup-
             ports 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.

NetBSD 10.99                   October 31, 2024                   NetBSD 10.99