I’ve read the rules several times to understand this, but I’d like a second opinion. We are out of Pneumatic Solenoid outputs.
Originally I was going to use Arduino relays to run a couple more pneumatic solenoids. They would be connected to the relay outputs on the roborio and powered from the VRM 12V 500MA rail, but it appears that will not be legal because of the way the rules are written.
Am I right in thinking I HAVE to use Spike relays?
R47 says all circuits must be powered by the PD board. You can power one PCM off the PCM terminals on the end of the PD board (R54). That fuse is also used for the radio so I think it is a bad idea to power the PCM with a compressor on it as well, You allowed one PCM per breaker per R58. The way I read all this is you cannot power the PCM from a VCM.
I think you could use the old KOP “Spike” relays, every established team has a box overflowing with them. [Youngsters: we ran pneumatic solenoids with Spikes in the IFI, pre-cRIO era.] Check the rules, you may be able to branch several from one PD port, of which you have zero spare unfortunately. And control the Spikes from the four roboRIO relay outputs.