I'm working on a project that requires that I analyze a signal from the parallel port of my computer and use it to turn on relays. There are about 19 relays to control, and I designed all the gates to get each one on, but there is a problem with keeping them on when I output to turn on another relay. Ideally, here is what I want:
pins 1 and 2 control one relay(not really, but for ease in explanation, they do). pin 1 is high and pin 2 is low. The pins both go to some gate and the output is low. Now turn pin 2 high, and the gate output is high. Now turn pin 2 low and the gate output remains high. Finally, turn pin 1 low and the gate output goes low. Thus, pin 1 controls whether or not it will work at all, and pin 2 only initiates it but will let it continue to work when turned off.
I've been wracking my brain for ways to get this to work and I'm stumped. Please help if you have any suggestions.
bob
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