6502ASM

Assembler for the MOS 6502 processor

Build

mkdir 6502ASM/build
cd 6502ASM/build
cmake ..
make -j

Usage

ASM6502 <asmfile> [-a] [-b] [-p <progfile>]

-a: output assembly and machine code bytes

-b: output C64 basic program that pokes machine code into RAM

-p <progfile>: write machine code into a progfile (C64 .PRG)

6502ASM examples/frame.asm produces

--- 6502 Machine Code ---
                                    .ORG $C000
0xc000:0xa0,0x00                    LDY #0
0xc002:0x8c,0x20,0xd0   label:      STY $D020
0xc005:0xc8                         INY
0xc006:0xd0,0xfa                    BNE label
0xc008:0x60                         RTS

--- Commodore Basic Initializer Listing ---
100 read nb
110 for bi = 1 to nb
120 read addr
130 read nby
140 for byi = 1 to nby
150 read byvl
160 poke addr+byi-1, byvl
170 next byi
180 next bi
190 end
200 rem number of mem blocks
210 data 1
220 rem block start number bytes
230 data 49152, 9
240 data 160,  0,140, 32
250 data 208,200,208,250
260 data  96

ToDos

• Test for all ASM commands including all addressing modes