312
2486AA–AVR–02/2013
ATmega8(L)
Mnemonics
Operands
Description
Operation
Flags
#Clocks
BRIE
k
Branch if Interrupt Enabled
if ( I = 1) then PC
PC + k + 1
None
1 / 2
BRID
k
Branch if Interrupt Disabled
if ( I = 0) then PC
PC + k + 1
None
1 / 2
DATA TRANSFER INSTRUCTIONS
MOV
Rd, Rr
Move Between Registers
Rd
Rr
None
1
MOVW
Rd, Rr
Copy Register Word
Rd+1:Rd
Rr+1:Rr
None
1
LDI
Rd, K
Load Immediate
Rd
KNone
1
LD
Rd, X
Load Indirect
Rd
(X)
None
2
LD
Rd, X+
Load Indirect and Post-Inc.
Rd
(X), X X + 1
None
2
LD
Rd, - X
Load Indirect and Pre-Dec.
X
X - 1, Rd (X)
None
2
LD
Rd, Y
Load Indirect
Rd
(Y)
None
2
LD
Rd, Y+
Load Indirect and Post-Inc.
Rd
(Y), Y Y + 1
None
2
LD
Rd, - Y
Load Indirect and Pre-Dec.
Y
Y - 1, Rd (Y)
None
2
LDD
Rd,Y+q
Load Indirect with Displacement
Rd
(Y + q)
None
2
LD
Rd, Z
Load Indirect
Rd
(Z)
None
2
LD
Rd, Z+
Load Indirect and Post-Inc.
Rd
(Z), Z Z+1
None
2
LD
Rd, -Z
Load Indirect and Pre-Dec.
Z
Z - 1, Rd (Z)
None
2
LDD
Rd, Z+q
Load Indirect with Displacement
Rd
(Z + q)
None
2
LDS
Rd, k
Load Direct from SRAM
Rd
(k)
None
2
ST
X, Rr
Store Indirect
(X)
Rr
None
2
ST
X+, Rr
Store Indirect and Post-Inc.
(X)
Rr, X X + 1
None
2
ST
- X, Rr
Store Indirect and Pre-Dec.
X
X - 1, (X) Rr
None
2
ST
Y, Rr
Store Indirect
(Y)
Rr
None
2
ST
Y+, Rr
Store Indirect and Post-Inc.
(Y)
Rr, Y Y + 1
None
2
ST
- Y, Rr
Store Indirect and Pre-Dec.
Y
Y - 1, (Y) Rr
None
2
STD
Y+q,Rr
Store Indirect with Displacement
(Y + q)
Rr
None
2
ST
Z, Rr
Store Indirect
(Z)
Rr
None
2
ST
Z+, Rr
Store Indirect and Post-Inc.
(Z)
Rr, Z Z + 1
None
2
ST
-Z, Rr
Store Indirect and Pre-Dec.
Z
Z - 1, (Z) Rr
None
2
STD
Z+q,Rr
Store Indirect with Displacement
(Z + q)
Rr
None
2
STS
k, Rr
Store Direct to SRAM
(k)
Rr
None
2
LPM
Load Program Memory
R0
(Z)
None
3
LPM
Rd, Z
Load Program Memory
Rd
(Z)
None
3
LPM
Rd, Z+
Load Program Memory and Post-Inc
Rd
(Z), Z Z+1
None
3
SPM
Store Program Memory
(Z)
R1:R0
None
-
IN
Rd, P
In Port
Rd
PNone
1
OUT
P, Rr
Out Port
P
Rr
None
1
PUSH
Rr
Push Register on Stack
STACK
Rr
None
2
POP
Rd
Pop Register from Stack
Rd
STACK
None
2
BIT AND BIT-TEST INSTRUCTIONS
SBI
P,b
Set Bit in I/O Register
I/O(P,b)
1None
2
CBI
P,b
Clear Bit in I/O Register
I/O(P,b)
0None
2
LSL
Rd
Logical Shift Left
Rd(n+1)
Rd(n), Rd(0) 0
Z, C, N, V
1
LSR
Rd
Logical Shift Right
Rd(n)
Rd(n+1), Rd(7) 0
Z, C, N, V
1
ROL
Rd
Rotate Left Through Carry
Rd(0)
C,Rd(n+1) Rd(n),CRd(7)
Z, C, N, V
1
ROR
Rd
Rotate Right Through Carry
Rd(7)
C,Rd(n) Rd(n+1),CRd(0)
Z, C, N, V
1
ASR
Rd
Arithmetic Shift Right
Rd(n)
Rd(n+1), n=0..6
Z, C, N, V
1
SWAP
Rd
Swap Nibbles
Rd(3..0)
Rd(7..4),Rd(7..4)Rd(3..0)
None
1
BSET
s
Flag Set
SREG(s)
1
SREG(s)
1
BCLR
s
Flag Clear
SREG(s)
0
SREG(s)
1
BST
Rr, b
Bit Store from Register to T
T
Rr(b)
T
1
BLD
Rd, b
Bit load from T to Register
Rd(b)
TNone
1
SEC
Set Carry
C
1C
1
CLC
Clear Carry
C
0
C
1
SEN
Set Negative Flag
N
1N
1
CLN
Clear Negative Flag
N
0
N
1
SEZ
Set Zero Flag
Z
1Z
1
CLZ
Clear Zero Flag
Z
0
Z
1
SEI
Global Interrupt Enable
I
1I
1
CLI
Global Interrupt Disable
I
0
I
1
SES
Set Signed Test Flag
S
1S
1
CLS
Clear Signed Test Flag
S
0
S
1
SEV
Set Twos Complement Overflow.
V
1V
1
CLV
Clear Twos Complement Overflow
V
0
V
1
SET
Set T in SREG
T
1T
1
Instruction Set Summary (Continued)