OWSBM(4) FreeBSD Kernel Interfaces Manual OWSBM(4)
NAME
owsbm - 1-Wire smart battery monitor device
SYNOPSIS
owsbm* at onewire?
DESCRIPTION
The owsbm driver provides support for the 1-Wire smart battery monitor.
The sensor possesses a temperature sensor, an A/D converter for measuring
both battery voltage and current, a current accumulator of both incoming
and outgoing current, an elapsed time and 40 bytes of nonvolatile EEPROM.
Only the three voltages (VDD, VAD, CR) and temperature are accessible by
the sysctl(8) interface.
The following chips are supported by the driver:
o Maxim/Dallas DS2438
MEASURING CURRENT
The sensor does not measure current directly. Instead it measures the
voltage across the Rsens pins.
I = Voltage CR / Rsens (where Rsens is in Ohms)
SEE ALSO
intro(4), onewire(4), owtemp(4), sysctl(8)
HISTORY
The owsbm driver first appeared in OpenBSD 4.1.
AUTHORS
The owsbm driver was written by Aaron Linville <
[email protected]>.
FreeBSD 14.1-RELEASE-p8 July 16, 2013 FreeBSD 14.1-RELEASE-p8