Opcode Map
Table 4-1. Instruction Set Summary
Effect on
CCR
Source
Form
Operation
Description
V H I N Z C
AND #opr
AND opr
AND opr
AND opr,X
AND opr,X
AND ,X
AND opr,SP
AND opr,SP
IMM
DIR
EXT
IX2
IX1
IX
A4
B4
C4
D4
E4
F4
ii
2
3
4
4
3
2
4
5
dd
hh ll
ee ff
ff
Logical AND
A ← (A) & (M)
0
–
–
–
–
o
o
o
o
–
SP1
SP2
9EE4 ff
9ED4 ee ff
ASL opr
ASLA
ASLX
ASL opr,X
ASL ,X
ASL opr,SP
DIR
INH
INH
IX1
IX
38
48
58
68
78
dd
ff
4
1
1
4
3
5
Arithmetic Shift Left
(Same as LSL)
o
o
o
C
0
b7
b0
b0
SP1
9E68 ff
ASR opr
ASRA
ASRX
ASR opr,X
ASR opr,X
ASR opr,SP
DIR
INH
INH
IX1
IX
37
47
57
67
77
dd
4
1
1
4
3
5
C
Arithmetic Shift Right
o
–
–
–
–
o
o
ff
b7
SP1
9E67 ff
BCC rel
Branch if Carry Bit Clear
PC ← (PC) + 2 + rel ? (C) = 0
–
–
–
– REL
24
rr
3
DIR (b0)
11
13
15
17
19
1B
1D
1F
dd
dd
dd
dd
dd
dd
dd
dd
4
4
4
4
4
4
4
4
DIR (b1)
DIR (b2)
DIR (b3)
DIR (b4)
DIR (b5)
DIR (b6)
DIR (b7)
BCLR n, opr
Clear Bit n in M
Mn ← 0
–
–
–
–
–
–
BCS rel
BEQ rel
Branch if Carry Bit Set (Same as BLO)
Branch if Equal
PC ← (PC) + 2 + rel ? (C) = 1
PC ← (PC) + 2 + rel ? (Z) = 1
–
–
–
–
–
–
–
–
–
–
– REL
– REL
25
27
rr
rr
3
3
Branch if Greater Than or Equal To
(Signed Operands)
BGE opr
BGT opr
PC ← (PC) + 2 + rel ? (N ⊕ V) = 0
–
–
–
–
–
–
–
–
–
– REL
– REL
90
92
rr
rr
3
Branch if Greater Than (Signed
Operands)
PC ← (PC) + 2 +rel ? (Z) | (N ⊕ V)=0 –
3
3
BHCC rel
BHCS rel
BHI rel
Branch if Half Carry Bit Clear
Branch if Half Carry Bit Set
Branch if Higher
PC ← (PC) + 2 + rel ? (H) = 0
PC ← (PC) + 2 + rel ? (H) = 1
PC ← (PC) + 2 + rel ? (C) | (Z) = 0
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
– REL
– REL
– REL
28
29
22
rr
rr
rr
3
3
3
Branch if Higher or Same
(Same as BCC)
BHS rel
PC ← (PC) + 2 + rel ? (C) = 0
–
–
–
–
–
– REL
24
rr
BIH rel
BIL rel
Branch if IRQ Pin High
Branch if IRQ Pin Low
PC ← (PC) + 2 + rel ? IRQ = 1
PC ← (PC) + 2 + rel ? IRQ = 0
–
–
–
–
–
–
–
–
–
–
– REL
– REL
2F
2E
rr
rr
3
3
MC68HC908AP Family Data Sheet, Rev. 4
Freescale Semiconductor
61