No value in digital ins using NASON pressure switch.

[Ari Allyn-Feuer]

Hi.

Like many teams, 753 is attempting to control the pneumatic compressor using the NASON pressure switch, running it when the switch reports low pressure and shutting off when the switch reports 115 PSI. I am not our main programmer, (that's Katherine McAuliffe AKA CrossedHeart), but am a fairly close second, and the sensors specialist. I am conversant in variables, loops, arrays, and syntax in C++, and am capable of using the camera variables and setting the PWMs and relays and such, but I ran into what appears a clean break between output and input signal in attempting to use the NASON pressure switch.

After experiments in controlling the compressor and other items on SPIKEs on the relays, I am able to control the relay outputs and make the compressor obey commands. But when I used a conditionality loop to run it based on the input from the digital in 1, it didn't respond, but ran forever as if the switch never opened.

I tested the switch with an ohmmeter, and it reported the proper continuity at the proper pressures. I made sure it was wired the way specified in the FIRST documents, and that pressure from the compressor was reaching the valve, and that the return logic operated in the way I thought (1=continuity, 0=ground). I tried reversing and modifying my conditionality loop in many different ways to see if it was causing the problem, and used the compressor code provided by FIRST. None of it worked, so i ordered a printf of the value coming from that input every loop. It returned nothing. I sandwiched it betwen two distinctive blocks of text so I could see it, but it failed to appear.

I have reached the conclusion that the digital in is not returning a value. Has someone else had and solved this problem? Do I need to initialize the Digital ins besides declaring them inputs in user initialization?

Eternal gratitude to any who helps me,

Ari Allyn-Feuer.

[Ari Allyn-Feuer]

Consider the question retracted. For all my long hours of testing, the switch cable lay passively plugged into the wrong digital in.

This is a confirmation of one of Murphy's many computer laws:

"In every case in which computer error is asserted, there are at least two human errors, including the error of blaming it on the computer."

Thanks anyway.

Ari Allyn-Feuer.