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       i2cget - read from I2C/SMBus chip registers


       i2cget [-f] [-y] i2cbus chip-address [data-address [mode]]
       i2cget -V


       i2cget  is a small helper program to read registers visible through the
       I2C bus (or SMBus).


       -V     Display the version and exit.

       -f     Force access to the device  even  if  it  is  already  busy.  By
              default,  i2cget will refuse to access a device which is already
              under the control  of  a  kernel  driver.  Using  this  flag  is
              dangerous,  it  can  seriously  confuse  the  kernel  driver  in
              question. It can also cause i2cget to return an  invalid  value.
              So  use at your own risk and only if you know what you’re doing.

       -y     Disable interactive mode. By default, i2cget  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. Use with caution.

       There  are  two required options to i2cget. i2cbus indicates the number
       or name 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  0x03  and

       data-address specifies the address on that chip to read from, and is an
       integer between  0x00  and  0xFF.  If  omitted,  the  currently  active
       register will be read (if that makes sense for the considered chip).

       The  mode  parameter,  if  specified,  is one of the letters b, w or c,
       corresponding to a read  byte  data,  a  read  word  data  or  a  write
       byte/read  byte  transaction, respectively. A p can also be appended to
       the mode parameter to enable PEC. If the  mode  parameter  is  omitted,
       i2cget defaults to a read byte data transaction, unless data-address is
       also omitted, in which case the default (and only valid) transaction is
       a single read byte.


       i2cget can be extremely dangerous if used improperly. I2C and SMBus are
       designed in such a way that an SMBus read transaction can be seen as  a
       write  transaction  by  certain  chips.  This  is  particularly true if
       setting mode to cp  (write  byte/read  byte  with  PEC).  Be  extremely
       careful using this program.


       i2cdump(8), i2cset(8)


       Jean Delvare

       This  manual  page  was strongly inspired from those written by David Z
       Maze for i2cset.

                                   May 2008