Reprogramming existing paintball circuit boards (PIC-based)

[sumorai]

Once I made my GCode project public I had a few friends ask me if I could put my code on their existing guns. The most common request was to reprogram cocker boards with newer features. I've started teaching myself about PIC processors, and picked up a few of them, as well as a PIC programmer device, in order to do this.

I've now separated this project out from the GCode thread so I can continue this discussion/log separately.

I've been doing a whole lot of googling, and also reading through this old PIC book which I picked up years ago when I first became curious about paintball gun circuit boards and programming them. It's a bit out of date now, but the architecture and instructions haven't really changed much.

Ideally, I'd like to eventually have a version of GCode for PIC processors as well. There'd have to be a version targeted at each specific board, though, as individual PIC microchip differences and the pin setups used on each board will vary greatly.

I'm using MPLAB X with the XC8 compiler and a cheap USB PIC programmer, although I bought that just to try it out and play around, so when I really start working on this I'll likely grab a PICkit 3 since the ICP01 I'm using doesn't have debugging capabilities.

[neftaly]

I'm really off PICs myself. They were okay a decade ago, but I prefer chips like the MSP430 nowadays (the LaunchPad bridges the gap between an Arduino and something you'd use in production).

[sumorai]

I'd prefer to stick with Arduino for things I build myself due to the programming simplicity. BUT, I've had some requests to make my code work on boards that use PICs, so I'm looking into that. I'm going to give Pinguino a try on some PIC18F chips I have now.

[sumorai]

The code examples for that MSP stuff don't much simpler than PIC at all. What is it about them that is better?

[neftaly]

I hated having to code in assembly, looks like compilers are available now though. Obviously this depends on which silicon you use but on the MSP interrupts seem to "just work", generally more code space, better onboard functionality, 16 bit (though I see some sort of 16 bit PIC is now available... for 32 bit I prefer Cortex), dev board costs, easier to code (more modern architecture), etc. At the end of the day a lot of it is subjective though.

[sumorai]

Messing around with this PIC stuff so far makes me REALLY appreciate how simple Arduino is to deal with. I've at least got MPLAB X and the XC8 compiler chain installed and working now, and was able to compile and upload a test program directly to the PIC18F4550 I have.

I'm working on setting up a Pinguino board to try that with.

[neftaly]

I forgot about PICAXE, they had an affordable and palatable method of MCU prototyping & hobby work before Arduino. Penguino or a BASIC interpreter should work well though.

[sumorai]

BASIC. *shudder*

[Simon]

I used to program in basic when I was 10

[sumorai]

Yeah, I've spent some time with it in the past. My first programming class in junior high was in BASIC. The first PIC setup I had about 6 years ago was a PIC BASIC Stamp. I'd really prefer to program in C, or even in assembly.