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55 lines
1.2 KiB
Markdown
55 lines
1.2 KiB
Markdown
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# About
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Attempts to translate x86 assembly into mos6502 assembly.
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# Why?
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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.
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# Example
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After compilation (requires a full C++14 compiler), you can run something like this:
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```assembly_x86
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// test.asm
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main:
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movb $1, 53280
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xorl %eax, %eax
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ret
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```
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```bash
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cat test.asm | x86-to-6502
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```
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And get this output:
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```
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main:
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ldy #$1
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sty 53280
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lda $00
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rts
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```
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# Caveats
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* Nothing is guaranteed. This could break your computer. Who knows?
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* All values are truncated to 8 bit. We have no support for 16bit math or pointers yet
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* Only as many instructions are supported as I have needed to support to get my test cases working
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# To Do
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*Everything*
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Well, lots of things.
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* Better / more efficient translation
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* Support for 16bit math? Maybe? We need to at least be able to do 16bit pointer math
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* Consider supporting the "Sweet 16" virtual 16bit CPU that Woz designed?
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* 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?
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* Support for more CPU instructions
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* A test suite
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