NT6881
Instruction Set List (contiuned)
Instruction Code
Meaning
Operation
LDA
LDX
LDY
LSR
Load accumulator with memory
Load index register X with memory
Load index register Y with memory
Shift right one bit
M → A
M → X
M → Y
0 → M7‧ ‧ ‧ M0 → C
NOP
ORA
No operation
Logical OR
No operation (2 cycles)
A + M → A
PHA
PHP
PLA
PLP
ROL
ROR
RTI
Push accumulator on stack
Push status register on stack
Pull accumulator from stack
Pull status register from stack
Rotate left through carry
A ↓
P ↓
A ↑
P ↑
C ← M7‧ ‧ ‧ M0 ← C
C → M7‧ ‧ ‧ M0 → C
P ↑，PC ↑
PC ↑，PC+1 → PC
A － M － C → A，C
1 → C
Rotate right through carry
Return from interrupt
RTS
SBC
SEC
SED
SEI
Return from subroutine
Subtract with borrow
Set carry
Set decimal mode
1 → D
Set interrupt disable status
Store accumulator in memory
Store index register X in memory
Store index register Y in memory
Transfer accumulator to index X
Transfer accumulator to index Y
Transfer stack pointer to index X
Transfer index X to accumulator
Transfer index X to stack pointer
Transfer index Y to accumulator
1 → I
STA
STX
STY
TAX
TAY
TSX
TXA
A → M
X → M
Y → M
A → X
A → Y
S → X
X → A
TXS
X → S
TYA
Y → A
* For more detailed specifications, please refer to 6502 programming data book.
6
ETC [ ETC ]
