NT6881
2.Instruction Set List
Instruction Code
Meaning
Add with carry
Logical AND
Operation
ADC
AND
ASL
BCC
BCS
BEQ
BIT
A + M + C → A，C
A‧ M → A
Shift left one bit
C ← M7‧ ‧ ‧ M0 ← 0
Branch on C＝0
Branch on C＝1
Branch on Z＝1
A‧ M，M7 → N，M6 → V
Branch on N＝1
Branch on Z＝0
Branch on N＝0
Forced interrupt PC + 2↓ PC↓
Branch on V＝0
Branch on V＝1
0 → C
Branch if carry clear
Branch if carry set
Branch if equal to zero
Bit test
BMI
BNE
BPL
BRK
BVC
BVS
CLC
CLD
CLI
Branch if minus
Branch if not equal to zero
Branch if plus
Break
Branch if overflow clear
Branch if overflow set
Clear carry
Clear decimal mode
Clear interrupt disable bit
Clear overflow
0 → D
0 → I
CLV
CMP
CPX
CPY
DEC
DEX
DEY
EOR
INC
0 → V
Compare accumulator to memory
Compare with index register X
Compare with index register Y
Decrement memory by one
Decrement index X by one
Decrement index Y by one
Logical exclusive-OR
Increment memory by one
Increment index X by one
Increment index Y by one
Jump to new location
Jump to subroutine
A － M
X － M
Y － M
M － 1 → M
X － 1 → X
Y － 1 → Y
A ⊕ M→A
M + 1 → M
INX
X + 1 → X
INY
Y + 1 → Y
JMP
JSR
(PC + 1) → PCL，(PC + 2) → PCH
PC + 2↓，(PC + 1) → PCL，(PC + 2) → PCH
5
ETC [ ETC ]
