I do real-time controls programming and I control a relay in a python program that must be turned off before the program ends. First, the program should never exit unless I do it explicitly. Is there a 'hook' to process before any exit (even if not expected). I must turn off that relay or harm may occur. Thanks, Doug
Well, the harm is running down a solar battery bank and shortening the life of the batteries. The relay that runs the inverter fed by the batteries needs to turn off at a particular battery voltage level and within several minutes. So, not time critical and not devastating consequences. Given these circumstances, is there a point I can run some code on any exit? I have decided to use a missing pulse circuit with a 2n3906 and 555 timer, so that missing a pulse train will shut off the inverter. Then if Python stops sending the 'watchdog' pulses, the inverter shuts down. Still, I would like to know if a 'hook' exists on exit from Python. I am running Linux on a Raspberry Pi with Python 2.7.4 I also run an Apache server on the Pi for monitor and control of power, HVAC, and security. Thanks, Doug _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
