NAME

       comedi_calibrate - COMEDI calibration utility

SYNOPSIS

       comedi_calibrate [-f /dev/comediN]

DESCRIPTION

       comedi_calibrate  is  used  to  autocalibrate  comedi  devices.   Some comedi devices have the ability to
       measure internal stable voltage references and control gains and offsets  using  programmable  DACs.   On
       these  devices,  comedi_calibrate  determines the proper values to feed into the programmable calibration
       DACs.   These  calibration   settings   are   then   saved   to   a   file,   which   can   be   fed   to
       comedi_apply_calibration() and related functions.

       If comedi_calibrate finds an existing calibration file, it will not perform a new calibration by default.
       It will simply read its calibration information from the file.  This behaviour may be overridden with the
       --calibrate option, to force a new calibration to be performed.

       After obtaining the calibration information for the board, comedi_calibrate will then apply a calibration
       setting  appropriate  for  the specified subdevice, channel, and range (see the --subdevice , --channel ,
       and --range options below).  See the comedilib  documentation  for  comedi_apply_calibration()  for  more
       information.

       comedi_calibrate prints a lot of debugging information as it runs.

LIMITATIONS

       comedi_calibrate  only  works  on  boards  that  it  understands.   For  boards  that  are  known to have
       autocalibration ability, but are not currently supported, comedi_calibrate will  output  basic  debugging
       information  that  is  useful  for the author to add support for your device.  Please send this output to
       him.

EXAMPLES

       comedi_calibrate --file /dev/comediN
              If no default calibration for /dev/comediN already exists, perform a calibration and save  results
              to default location.

       comedi_calibrate --calibrate
              Perform a calibration, using existing calibration (if it exists) as starting point.

       comedi_calibrate --reset --calibrate
              Perform a fresh calibration and save results to default location.

       comedi_calibrate --no-calibrate --subdevice subd.BI--range range --save-file cal_file
              Apply  calibration  for  subdevice  subd,  range range, using the settings in the calibration file
              cal_file.

OPTIONS

       comedi_calibrate recognizes the following options:

       -a aref, --aref aref
              Along with  --channel,  --range  and  --subdevice,  this  specifies  which  calibration  you  want
              comedi_calibrate leave applied to the board.  The default is 0.

       --[no-]calibrate
              Force  calibration to be performed (or not).  By default, comedi_calibrate will only perform a new
              calibration if no existing calibration file is found (see --save-file).

       -c channel,--channel channel
              Along  with  --subdevice,  --range  and  --aref,  this  specifies  which  calibration   you   want
              comedi_calibrate to leave applied to the board.  The default is 0.

       --[no-]dump
              Perform  (or  not)  dump of various information about state of calibration prior to performing new
              calibration.

       -f /dev/comediN,--file /dev/comediN
              Perform calibration on device /dev/comediN.

       --help Print help for options then exit.

       -q, --quiet
              Don't generate output to stdout.

       -r range, --range range
              Along  with  --channel,  --subdevice  and  --aref,  this  specifies  which  calibration  you  want
              comedi_calibrate to leave applied to the board.  The default is 0.

       --[no-]reset
              Reset  (or  don't  reset)  calibration  subdevice to a reasonable starting point before performing
              calibration.  The default is --no-reset.  If --no-reset is used, the calibration routine will  try
              to  use an existing calibration (see --save-file) as a starting point.  This is useful if a single
              calibration pass is not sufficient, and you wish to perform another calibration pass starting from
              the results of the previous pass.

       --[no-]results
              Perform (or not) dump of various information about  state  of  calibration  after  performing  new
              calibration.

       -S file, --save-file file
              Save  calibration information to specified file, instead of default location.  If the file already
              exists, comedi_calibrate will also use its contents as a starting point for the  calibration  pass
              (see --no-reset).

       -s subdevice, --subdevice subdevice
              Along   with   --channel,   --range   and  --aref,  this  specifies  which  calibration  you  want
              comedi_calibrate to leave applied to the board.  The default is 0.

       -v, --verbose
              Generate more verbose output to stdout, can be specified multiple times

SEE ALSO

       comedi(7)

VERSION

       0.7.x

AUTHOR

       David Schleef, <ds@schleef.org>

       Frank Mori Hess, <fmhess@users.sourceforge.net>

                                                                                             comedi_calibrate(8)