Programming Jabber

The calibrate() function

The calibrate() function is called if the script is started without the -l option. This function simply prints a message, waits for the user to press Enter, and then goes into a a gentle loop, emitting whatever value was polled from the light sensor so the user can determine the pivot point:

sub calibrate {
  my $rcx = shift;

  print <<EOT;
Calibration mode.
Note the sensor values and decide on a 'pivot' value
above which 'no coffee' is signified and below which
'coffee' is signified.

End the calibration mode with Ctrl-C.

Press Enter to start calibration...
EOT

  <STDIN>;

  while (1) {
    print $rcx->Poll(9, SENSOR), " ";
    sleep 1;
  }

}

The output produced from this function can be seen in Figure 9-4.