Hacking on the GBA gave me the motivation to learn embedded programming in C. You need to know how to handle memory-mapped registers, create C structs with prop

Hacking on the GBA gave me the motivation to learn embedded programming in C. You need to know how to handle memory-mapped registers, create C structs with proper alignment to interface with the hardware sprite/tile acceleration, direct memory access, and how to manipulate GCC to do things like override functions with BIOS functions or build freestanding binaries with custom chunks of boot assembler. This sounds intimidating as hell, but it is a fantastic motivator to learn these things to see your own little animation on actual game hardware.