Project Support

pon (Power ON detector voltages)

When spelled as one word with three letters, pon and pof specifically refer to applying "high" (potentially damaging, if wrong) voltages to a detector. The pon command may or may not be configured to use the PONFITS setting in config for reference voltages and clocking patterns from a previously saved exposure. Before issuing pon the controller must have stage2 embedded code loaded. It is only necessary to issue this command once.

Before removing main power from the system, issuing a reset or stage2 detector voltages should be off first by using the pof command. If this is not done, the controllers DACs will continue to supply power to the detector, and turning off main power may not result in the cleanest power-off system to ensure maximum safety for the detector.

pon fake

Some devices take a long time to settle after having voltages removed and re-applied. It is possible to boot into a different (e.g., for development/testing) stage2 and keep voltages applied to the detector by ignoring the advice above and simply issuing stage2 without powering off the detector first. After the controller reboots, do not issue pon because most implementation of pon first remove voltages before re-applying. The special syntax:

pon fake

will restore clocking patterns without disturbing detector voltages (if supported on the system.)