Forgot about the MemoryThe game was progressing nicely, I got a scrolled map loaded from file, a pixel that can walk around it and shoot other pixels, etc. — but then I decided to try and see if I can run it on the actual hardware. Guess what. Out of memory error.
Don't worry, though, because I can put a lot of stuff on the flash. It's not like the disk on the PC — it's almost as fast to access as the RAM. I think I will start with the level map, as that's the biggest thing.
I might also revise my approach to programming this. I somehow naturally levitated towards using objects and classes, because that gives you nice organisation, but on such a limited platform that is really wasteful. For a start I will use slots on the classes, and if that doesn't help, I will rewrite the whole thing into more a procedural way.