A C64 Game - Step 1


Today's development is heaps and bounds beyond imagination from 20 years ago. I've always had a soft spot for the C64 after all this years. So I sat down and tried to start assembly programming on a C64.

Today I'll start with a sort of tutorial on how to write a C64 game. I have prepared 36 steps for now, planned are probably a few more.

I'll start out very small but there will be bigger steps later on. The code is supposed to be heavily commented but is probably not clear for everyone. I'll be happy to answer questions regarding the code. The code is written for the ACME cross compiler, which allows to compile the code on any bigger OS.

Step #1 is a simple base for a game. It provides a Basic start (10 SYS 2064), sets up the VIC relocation and shows a simple synchronized game loop.

To show the loop running the border color is flashed and the top left char is rotating throughout all characters.

The not too eye-popping result looks like this:

Find here the source code and binary for use in an emulator of your choice (I recommend WinVICE):