NAME

       i2cdetect - detect I2C chips

SYNOPSIS

       i2cdetect [-y] [-a] [-q|-r] i2cbus [first last]
       i2cdetect -F i2cbus
       i2cdetect -V
       i2cdetect -l

DESCRIPTION

       i2cdetect  is  a userspace program to scan an I2C bus for devices. It outputs a table with
       the list of detected devices on the specified bus.  i2cbus indicates the number or name of
       the  I2C bus to be scanned, and should correspond to one of the busses listed by i2cdetect
       -l.  The optional parameters first and last restrict the  scanning  range  (default:  from
       0x03 to 0x77).

       i2cdetect can also be used to query the functionalities of an I2C bus (see option -F.)

WARNING

       This program can confuse your I2C bus, cause data loss and worse!

INTERPRETING THE OUTPUT

       Each cell in the output table will contain one of the following symbols:

       • "--". The address was probed but no chip answered.

       • "UU".  Probing  was  skipped, because this address is currently in use by a driver. This
         strongly suggests that there is a chip at this address.

       • An address number in hexadecimal, e.g. "2d" or "4e". A chip was found at this address.

OPTIONS

       -y     Disable interactive mode. By default, i2cdetect 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.

       -a     Force scanning of non-regular addresses. Not recommended.

       -q     Use SMBus "quick write" commands for probing (by default, the command used  is  the
              one believed to be the safest for each address).  Not recommended. This is known to
              corrupt the Atmel AT24RF08 EEPROM found on many IBM Thinkpad laptops.

       -r     Use SMBus "read byte" commands for probing (by default, the command used is the one
              believed  to  be  the  safest for each address).  Not recommended. This is known to
              lock SMBus on various write-only chips (most notably clock chips at address 0x69).

       -F     Display the list of functionalities implemented by the adapter and exit.

       -V     Display the version and exit.

       -l     Output a list of installed busses.

SEE ALSO

       i2cdump(8), sensors-detect(8)

AUTHOR

       Frodo Looijaard, Mark D. Studebaker and Jean Delvare

       This manual page was originally written by Aurelien Jarno  <aurel32@debian.org>,  for  the
       Debian GNU/Linux system.

                                            April 2008                               I2CDETECT(8)