mirror of
https://github.com/catseye/SixtyPical.git
synced 2024-11-22 01:32:13 +00:00
116 lines
2.5 KiB
Markdown
116 lines
2.5 KiB
Markdown
|
6502 Opcodes
|
||
|
============
|
||
|
|
||
|
As used or unused in SixtyPical.
|
||
|
|
||
|
### ld ###
|
||
|
|
||
|
ld a, 123 → LDA #123
|
||
|
ld a, lives → LDA LIVES
|
||
|
ld x, 123 → LDX #123
|
||
|
ld x, lives → LDX LIVES
|
||
|
ld y, 123 → LDY #123
|
||
|
ld y, lives → LDY LIVES
|
||
|
ld x, a → TAX
|
||
|
ld y, a → TAY
|
||
|
ld a, x → TXA
|
||
|
ld a, y → TYA
|
||
|
|
||
|
### st ###
|
||
|
|
||
|
st a, lives → STA LIVES
|
||
|
st x, lives → STX LIVES
|
||
|
st y, lives → STY LIVES
|
||
|
st on, c → SEC
|
||
|
st off, c → CLC
|
||
|
|
||
|
### add dest, src ###
|
||
|
|
||
|
add a, delta → ADC DELTA
|
||
|
add a, 1 → ADC #1
|
||
|
|
||
|
### inc ###
|
||
|
|
||
|
inc x → INX
|
||
|
inc y → INY
|
||
|
inc lives → INC LIVES
|
||
|
|
||
|
### sub ###
|
||
|
|
||
|
sub a, delta → SBC DELTA
|
||
|
sub a, 1 → SBC #1
|
||
|
|
||
|
### dec ###
|
||
|
|
||
|
dec x → DEX
|
||
|
dec y → DEY
|
||
|
dec lives → DEC LIVES
|
||
|
|
||
|
### cmp ###
|
||
|
|
||
|
cmp a, delta → CMP DELTA
|
||
|
cmp a, 1 → CMP #1
|
||
|
cmp x, 1 → CPX #1
|
||
|
cmp y, 1 → CPY #1
|
||
|
|
||
|
### and, or, xor ###
|
||
|
|
||
|
and a, 8 → AND #8
|
||
|
or a, 8 → ORA #8
|
||
|
xor a, 8 → EOR #8
|
||
|
|
||
|
### shl, shr ###
|
||
|
|
||
|
shl <dest-memory-location>
|
||
|
shr <dest-memory-location>
|
||
|
|
||
|
shl a → ROL A
|
||
|
shl lives → ROL LIVES
|
||
|
shr a → ROR A
|
||
|
shr lives → ROR LIVES
|
||
|
|
||
|
### call ###
|
||
|
|
||
|
call routine → JSR ROUTINE
|
||
|
|
||
|
### if ###
|
||
|
|
||
|
if z → BEQ LABEL
|
||
|
if not z → BNE LABEL
|
||
|
if n → BMI LABEL
|
||
|
if not n → BPL LABEL
|
||
|
if c → BCS LABEL
|
||
|
if not c → BCC LABEL
|
||
|
if v → BVS LABEL
|
||
|
if not v → BVC LABEL
|
||
|
|
||
|
### 6502 instructions unsupported ###
|
||
|
|
||
|
ASL Shift Left One Bit (Memory or Accumulator)
|
||
|
LSR Shift Right One Bit (Memory or Accumulator)
|
||
|
|
||
|
BIT Test Bits in Memory with Accumulator
|
||
|
BRK Force Break
|
||
|
|
||
|
CLD Clear Decimal Mode
|
||
|
CLI Clear interrupt Disable Bit
|
||
|
CLV Clear Overflow Flag
|
||
|
|
||
|
NOP No Operation
|
||
|
|
||
|
JMP Jump to New Location // but may be generated as part of `if`
|
||
|
|
||
|
PHA Push Accumulator on Stack
|
||
|
PHP Push Processor Status on Stack
|
||
|
PLA Pull Accumulator from Stack
|
||
|
PLP Pull Processor Status from Stack
|
||
|
|
||
|
RTI Return from Interrupt
|
||
|
RTS Return from Subroutine
|
||
|
|
||
|
SED Set Decimal Mode
|
||
|
SEI Set Interrupt Disable Status
|
||
|
|
||
|
TSX Transfer Stack Pointer to Index X
|
||
|
TXS Transfer Index X to Stack Pointer
|