.TH comedi_calibrate 8 ""
.SH NAME
\fBcomedi_calibrate\fR - COMEDI calibration utility
.SH SYNOPSIS
\fBcomedi_calibrate\fR [-f /dev/comediN]
.br
.SH DESCRIPTION
\fBcomedi_calibrate\fR is used to autocalibrate \fBcomedi\fR
devices.  Some \fBcomedi\fR devices have the ability to
measure internal stable voltage references and control
gains and offsets using programmable DACs.  On these devices,
\fBcomedi_calibrate\fR 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
.B \-\-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
.B \-\-subdevice
,
.B \-\-channel
, and
.B \-\-range
options below).  See the comedilib documentation for
comedi_apply_calibration() for more information.

\fBcomedi_calibrate\fR prints a lot of debugging information
as it runs.

.SH LIMITATIONS

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

.SH EXAMPLES

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

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

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

.TP
.BI comedi_calibrate\ \-\-no\-calibrate\ \-\-subdevice\  subd\
.BI              \-\-range\  range\  \-\-save\-file\  cal_file
Apply calibration for subdevice \fIsubd\fR, range \fIrange\fR, using
the settings in the calibration file \fIcal_file\fR.


.SH OPTIONS

\fBcomedi_calibrate\fR recognizes the following options:

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

.TP
.B \-\-[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 \fB--save-file\fR).

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

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

.TP
.BI \-f\  /dev/comediN, \-\-file\  /dev/comediN
Perform calibration on device \fB/dev/comediN\fR.

.TP
.B \-\-help
Print help for options then exit.

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

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

.TP
.B \-\-[no\-]reset
Reset (or don't reset) calibration subdevice to
a reasonable starting point before
performing calibration.  The default is \fB--no-reset\fR.  If
\fB--no-reset\fR is used, the calibration routine will try to use
an existing calibration (see \fB--save-file\fR) 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.

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

.TP
.BI \-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
\fB--no-reset\fR).

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

.TP
.B \-v, \-\-verbose
Generate more verbose output to stdout, can be specified multiple times


.SH SEE ALSO

\fBcomedi\fR(7)

.SH VERSION

0.7.x

.SH AUTHOR

David Schleef, <ds@schleef.org>

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