UTTORI ASM · IN DEVELOPMENT
6502X instruction catalog
Browse accepted 6502x instruction catalog mnemonics and addressing forms.
65xx.6502x adds these unofficial mnemonics on top of the documented set. NOP also gains extra operand forms. Aliases in parentheses are accepted spellings of the same canonical name.
| Mnemonic | What it does | Accepted operand forms |
|---|---|---|
ALR (ASR) |
AND then LSR. | #value |
ANC (AAC) |
AND. Copy N into C. | #value |
ANE (XAA) |
Unstable A AND X AND immediate. | #value |
ARR |
AND then ROR. | #value |
AXS (SBX) |
X = (A AND X) − immediate. | #value |
DCP (DCM) |
DEC then CMP. | zp, zp,x, addr, addr,x, addr,y, (zp,x), (zp),y |
ISC (ISB, INS) |
INC then SBC. | zp, zp,x, addr, addr,x, addr,y, (zp,x), (zp),y |
JAM (KIL, HLT) |
Halt the processor. | implied |
LAS (LAR) |
A, X, S = memory AND S. | addr,y |
LAX |
Load A and X. Immediate form is unstable. | #value, zp, zp,y, addr, addr,y, (zp,x), (zp),y |
RLA |
ROL then AND. | zp, zp,x, addr, addr,x, addr,y, (zp,x), (zp),y |
RRA |
ROR then ADC. | zp, zp,x, addr, addr,x, addr,y, (zp,x), (zp),y |
SAX (AAX) |
Store A AND X. | zp, zp,y, addr, (zp,x) |
SHA (AHX) |
Unstable store of A AND X AND (H+1). | addr,y, (zp),y |
SHX (SXA) |
Unstable store of X AND (H+1). | addr,y |
SHY (SYA) |
Unstable store of Y AND (H+1). | addr,x |
SLO |
ASL then ORA. | zp, zp,x, addr, addr,x, addr,y, (zp,x), (zp),y |
SRE (LSE) |
LSR then EOR. | zp, zp,x, addr, addr,x, addr,y, (zp,x), (zp),y |
TAS (SHS) |
Unstable S = A AND X. Store S AND (H+1). | addr,y |
Unstable forms emit a ca65-compatible byte and make no silicon-stability promise.