
293
7799D–AVR–11/10
ATmega8U2/16U2/32U2
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)
 T
None
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
CLT
Clear T in SREG
T
 0
T
1
SEH
Set Half Carry Flag in SREG
H
 1H
1
CLH
Clear Half Carry Flag in SREG
H
 0
H
1
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
 K
None
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
 P
None
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
MCU CONTROL INSTRUCTIONS
NOP
No Operation
None
1
SLEEP
Sleep
(see specific descr. for Sleep function)
None
1
WDR
Watchdog Reset
(see specific descr. for WDR/timer)
None
1
BREAK
Break
For On-chip Debug Only
None
N/A
Mnemonics
Operands
Description
Operation
Flags
#Clocks