i2cset - set I2C registers
i2cset [-y] i2cbus chip-address data-address value [mode] [mask]
i2cset is a small helper program to set registers visible through the
-V Display the version and exit.
-y Disable interactive mode. By default, i2cset will wait for a
confirmation from the user before messing with the I2C bus. When
this flag is used, it will perform the operation directly. This
is mainly meant to be used in scripts.
There are four required options to i2cset. i2cbus indicates the number
of the I2C bus to be scanned. This number should correspond to one of
the busses listed by i2cdetect -l. chip-address specifies the address
of the chip on that bus, and is an integer between 0x00 and 0x7F.
data-address specifies the address on that chip to write to, and is an
integer between 0x00 and 0xFF. value is the value to write to that
location on the chip.
The mode parameter, if specified, is one of the letters b or w, corre-
sponding to a write size of a single byte or a 16-bit word, respec-
tively. If the mode parameter is omitted, i2cset defaults to byte mode.
The value provided must be within range for the specified data type
(0x00-0xFF for bytes, 0x0000-0xFFFF for words).
The mask parameter, if specified, describes which bits of value will be
actually written to data-address. Bits set to 1 in the mask are taken
from value, while bits set to 0 will be read from data-address and thus
preserved by the operation.
i2cset can be extremely dangerous if used improperly. It can confuse
your I2C bus, cause data loss, or have more serious side effects. Writ-
ing to a serial EEPROM on a memory DIMM (chip addresses between 0x50
and 0x57) may DESTROY your memory, leaving your system unbootable! Be
extremely careful using this program.
Frodo Looijaard, Mark D. Studebaker, and the lm_sensors group
http://www.lm-sensors.nu/ This manual page was originally written by
David Z Maze <firstname.lastname@example.org> for the Debian GNU/Linux system. It was
then reviewed by the lm_sensors team and is now part of the lm_sensors
August 2004 I2CSET(8)
Man(1) output converted with