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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