Control filterwheel to select a specific filter. Also selects the clock source, and monitors the battery level.


This is part of my PhD camera system, for controlling the filter-wheel.
It is very specific to that particular system, and is irrelevant (and not usefully re-purposable) for any wider reuse.

filterctl -f 1287nm   Select the 1287nm filter.
filterctl -z   Power down the dewar light-gates and motor (for observation)
filterctl -k   Enable loopback mode
filterctl -c Ext   Set the clock source to Ext.
filterctl -M   Monitor the battery voltage, and alert when it dies.

The connected hardware consists of a USB/Parallel interface (ftdi245io) which controls a stepper motor via some optical fibres.
A filter-wheel is mounted upon the stepper motor (inside the dewar), such that one of 6 optical filters may be placed in front of the camera.
The filter-wheel's position can be read-back, using 3x light-gates.

When the dewar is quiescent, the 3 bit interface is re-purposed to monitor the battery voltage.

With the 3 remaining bits, the clock-source can be set to internal/external, and the divider may be varied: from 50Hz - 5kHz.

The dewar can be powered-up (lightgates on), down (lightgates off), or placed in loopback mode (temperature sensor + digital clock) connected to 2 of the 4 ADC inputs.


  • Documentation is in the README.txt, the man pages, and by invoking each command with -h. Or read the source (in PHP).
  • To install, simply: make && sudo make install
  • Note: there is also a dependency on ftdi245io
  • This is Free Software released under the GNU GPL v3+. Please feel free to take it, modify it, package it etc.
  • Author: Richard Neill. Do ask if you would like further information and assistance.


This was written as part of my PhD Infrared Camera system.
Whereas other programs are likely to be of use to the Internet community, cam2tiff is just part of my system documentation and bibliography.




Some selected files, from the tarball: Readme and Man-pages.


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