About
Attempts to translate x86 assembly into mos6502 assembly.
Why?
Why not? I figured I just barely knew some x86 and some 6502, so why not learn some more about both. Besides, this project can actually have some interesting applications.
Example
After compilation (requires a full C++14 compiler), you can run something like this:
// test.asm
main:
movb $1, 53280
xorl %eax, %eax
ret
cat test.asm | x86-to-6502
And get this output:
main:
ldy #$1
sty 53280
lda $00
rts
Caveats
- Nothing is guaranteed. This could break your computer. Who knows?
- All values are truncated to 8 bit. We have no support for 16bit math or pointers yet
- Only as many instructions are supported as I have needed to support to get my test cases working
To Do
Everything
Well, lots of things.
Better code organization
I really had no idea what I was doing when I started this. So, like all code, it's going to need some improvements along the way to make it more organized and more maintainable.
Improvements
- Keep track of input source lines and add comments in output to show where lines came from, for learning / debugging purposes
- Better / more efficient translation
- Support for 16bit math? Maybe? We need to at least be able to do 16bit pointer math
- Consider supporting the "Sweet 16" virtual 16bit CPU that Woz designed?
- Maybe for 16bit operation we try to detect if the input code is working on 8bit registers or 16+bit registers and do the right thing?
- Support for more CPU instructions
- A test suite