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)