I found the following "cheat sheet" I created when I began writing an assembler for the 6502:
Code:
INS T acc abs zpg imm abs,X abs,Y (aa,X) (aa),Y zpg,X zpg,Y (aaaa)
ADC I 6D 65 69 7D 79 61 71 75
AND I 2D 25 29 3D 39 21 31 35
ASL G 0A 0E 06 1E 16
BIT C 2C 24
CMP I CD C5 C9 DD D9 C1 D1 D5
CPX D EC E4 E0
CPY D CC C4 C0
DEC F CE C6 DE D6
EOR I 4D 45 49 5D 59 41 51 55
INC F EE E6 FE F6
JMP B 4C 6C
JSR A 20
LDA I AD A5 A9 BD B9 A1 B1 B5
LDX K AE A6 A2 BE B6
LDY L AC A4 A0 BC B4
LSR G 4A 4E 46 5E 56
ORA I 0D 05 09 1D 19 01 11 15
ROL G 2A 2E 26 3E 36
ROR G 6A 6E 66 7E 76
SBC I ED E5 E9 FD F9 E1 F1 F5
STA H 8D 85 9D 99 81 91 95
STX J 8E 86 96
STY E 8C 84 94
Type A - abs
Type B is a superset of type A - abs + indir
Type C is a superset of type A - abs + zpg
Type D is a superset of type C - abs + zpg + imm
Type E is a superset of type C - abs + zpg + zpg,X
Type F is a superset of type E - abs + zpg + zpg,X + abs,X
Type G is a superset of type F - abs + zpg + zpg,X + abs,X + acc
Type H is a superset of type F - abs + zpg + zpg,X + abs,X + abs,Y + (aa,X) + (aa),Y
Type I is a superset of type H - abs + zpg + zpg,X + abs,X + abs,Y + (aa,X) + (aa),Y + imm
Type J is a superset of type C - abs + zpg + zpg,Y
Type K is a superset of type J - abs + zpg + zpg,Y + abs,Y + imm
Type L is a superset of type F - abs + zpg + zpg,X + abs,X + imm
This includes only the NMOS 6502 instructions.
Do the new CMOS additions follow the same general scheme?
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