No, it won't short out the power supply. Theoretically it could, but I can tell you from experience that it won't.
You should be able to drive them high or low without any problems. The exception comes in with the Matrix2 board. Driving too high can cause some "erratic" behaviour. The controller expects a voltage between 0V and 1.6V. Driving to Vdd (~3V) is just too much some times.
As far as how rapid fire works,...
There are a few different ways. If you are only wanting to do rapid fire, then the easiest and probably most popular approach (at least on this site) is to toggle between Input and Output(Trigger Release).
So for instance let's say you are using a CG/CG2 style controller. Then driving the trigger high will simulate a trigger pull while driving the pin low will simulate a trigger release. We don't care about driving it high in this case though, because we are toggling between input and output-low.
So to simulate 10 Shots per second rapid fire you would have something like this.
while(1)
{
//Set RT to output
TRISIObits.TRISIOX = 0;
//Force trigger release
GPIObits.GPIOX = 0;
//Wait 50 ms
__delay_ms(50);
//Set RT to input
TRISIObits.TRISIOX = 1;
//Wait 50 ms
__delay_ms(50);
}
When the trigger is NOT being pulled then the mod toggles between "Releasing the trigger" and whatever the state of the trigger really is...which is a released trigger. So nothing happens.
When the trigger IS being pulled then the mod toggles between "Releasing the trigger" and the state of the trigger (which is pulled).
So this gives you rapid fire.
There are three other approaches that I know of though.
One is to use the Comparator to detect trigger pulls and then to respond in a macro fashion accordingly.
The another way is to use Analog to Digital conversion to detect the trigger pulls and then to respond.
And the last way is to use regular digital inputs to read the trigger pulls. (I don't recommend this way though.)
Note: Matrix/Matrix2 controllers are opposite of CG/CG2 for the triggers. Driving them high represents a trigger release while driving them low represents a trigger pull.
I hope this helps.
