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P.Svilans
09-03-2009, 15:52
Hi,

My team right now is having problems with the pressure switch...basically what happens is that we hook it up and the whole thing screws up. I'm guessing that it's not hooked up right (does something like that disable the whole control system?), or some wacky code that's running under the level I'm working with (somewhere deep down in the core classes?).

I'm pretty sure it's the hook up, but I'm just wondering if any other teams experienced any problems of the sort?

It's my schools first year in FIRST...

P.

EricVanWyk
09-03-2009, 15:55
One common mistake is to wire it between the 5V and 0V rails on the digital side car. This will short out that power supply, which will put it into a safety shutdown and cut all signals to your motor controllers.

Instead, you should wire it between signal and 0V. A resistor built into the digital sidecar will give it the "power" it needs.

P.Svilans
09-03-2009, 16:03
Thanks for the speedy response!

So do we need to put a jumper on the port we attach the pressure switch to, so it acts like a servo is attached? Because before when we tried to hook it up, we already had the white and black (Sig and (-) ) wires to the pressure switch...

P.

Alan Anderson
09-03-2009, 16:15
So do we need to put a jumper on the port we attach the pressure switch to, so it acts like a servo is attached?

That sounds like you're trying to connect the switch to a PWM port. Those ports are outputs only, for servos and speed controllers. You need to wire the switch to a set of DIGITAL I/O pins on the Digital Sidecar.

P.Svilans
09-03-2009, 16:22
Well then I really don't know what to do...We had it connected to the Digital I/O with the Sig(White), and (-)(Black). It still wouldn't work, and would cause the No Code problem on our Driver Station. We had to reimage the cRio every time we tried the pressure switch!
If anyone has any diagrams with exactly how and where every cable from the pressure switch needs to be connected then...it would be a life saver! Or at least narrow down the problems...

P.

P.

EricVanWyk
09-03-2009, 16:31
Ah ha! It is not possible to create a No Code error by miswiring your pressure switch (or anything else on the digital side car).

"No code" means that no user code is running on your cRIO. Try deploying the code, instead of running it. A quick search through these forums will tell you how to do that.

P.Svilans
09-03-2009, 16:47
Well...Sorry for wasting your time!

It was a wacky problem, since I don't know why it screwed up...and...well...it works! I'm pretty happy right now...but, it works! No idea how either! I just changed the Digital I/O port to which it's hooked up to from 1 to 10 or something, and...it works!

Thanks to everyone who helped anyways! It actually made us check the wiring...

P.