NAME

       sense_rec - Sense HAT data recorder

       Records  sensor  readings  from the Raspberry Pi Sense HAT in real time, outputting the results to a file
       for later playback or analysis. This is most useful for preparing records of experiments for use with the
       Sense HAT emulator. For example, a recording of a Sense HAT being dropped, a recording of a HAB flight, a
       recording of the cycle of temperature over a few days, etc.

SYNOPSIS

          sense_rec [-h] [--version] [-q] [-v] [-l FILE] [-P] [-c CONFIG]
                    [-d DURATION] [-f] output

DESCRIPTION

       -h, --help
              show this help message and exit

       --version
              show this program's version number and exit

       -q, --quiet
              produce less console output

       -v, --verbose
              produce more console output

       -l FILE, --log-file FILE
              log messages to the specified file

       -P, --pdb
              run under PDB (debug mode)

       -c FILE, --config FILE
              the Sense HAT configuration file to use (default: /etc/RTIMULib.ini)

       -d SECS, --duration SECS
              the duration to record for in seconds (default: record until terminated with Control-C)

       -i SECS, --interval SECS
              the delay between each reading in seconds (default: the  IMU  polling  interval,  typically  0.003
              seconds)

       -f, --flush
              flush  every  record  to  disk  immediately;  reduces chances of truncated data on power loss, but
              greatly increases disk activity

EXAMPLES

       To record an experiment with the Sense HAT, simply execute sense_rec with the filename you wish to record
       the results:

          $ sense_rec experiment.hat

       By default, the recording will continue indefinitely. Press Control-C to terminate the recording. If  you
       want  to  record  for  a  specific  duration,  you can use the --duration option to specify the number of
       seconds:

          $ sense_rec --duration 10 short_experiment.hat

       This tool can be run simultaneously with scripts that use the Sense HAT. Simply start your script in  one
       terminal,  then  open  another  to  start  sense_rec.  Alternatively, you can use the shell's job control
       facilities to start recording in the background:

          $ sense_rec experiment.hat &
          $ python experiment.py
          ...
          $ kill %1

       WARNING:
          Be aware that other scripts attempting to use the HAT's sensors will likely obtain different  readings
          than  they  would have if run standalone.  Some of the HAT's sensors are affected by their query-rate,
          and sense_rec drives all sensors at close to their maximum rate.

       If - is specified as the output file, sense_rec will write its output to stdout.  This  can  be  used  to
       reduce the disk space required for long output by piping the output through a compression tool like gzip:

          $ sense_rec - | gzip -c - > experiment.hat.gz

       When  compressed  in  this  manner the data typically uses approximately 3Kb per second (without gzip the
       recording will use approximately 10Kb of disk space per second). Use gunzip to de-compress the  data  for
       playback or analysis:

          $ gunzip -c experiment.hat.gz | sense_play -

       Another method of reducing the data usage is increasing the interval between readings (the default is the
       IMU  polling  interval  which  is  an  extremely  short 3ms). Obviously a longer interval will reduce the
       "fidelity" of the recording; you will only see the sensors  update  at  each  interval  during  playback,
       however  it  can  be  extremely  useful  for very long recordings. For example, to record with a 1 second
       interval between readings for 24 hours:

          $ sense_rec -i 1 -d $((24*60*60)) one_day_experiment.hat

       Finally, you can use pipes in conjunction with sense_csv to produce CSV output directly:

          $ sense_rec - | sense_csv - experiment.csv

       Be warned that CSV data is substantially larger than the binary format (CSV data uses approximately  25Kb
       per second at the default interval).

AUTHOR

       Raspberry Pi Foundation

COPYRIGHT

       2016-2021 Raspberry Pi Foundation

1.2                                               Sep 02, 2021                                      SENSE_REC(1)