AVR assembly instruction cheatsheet

Data Transfer

Instruction	Operands	Description	Operation
mov	Rd, Rr	Move Rr to Rd	`Rd = Rr`
ldi	Rd, K	Load K in Rd	`Rd = k`
	Rd must be from R16 to R31
ld	Rd, X	Load (X) in Rd	`Rd = *X`
	Rd, X+	Load (X) in Rd, X is incremented	`Rd = *X, X++`
	Rd, -X	X is decremented, Load ( X ) in Rd	`--X, Rd = X`
	All three registers can be used
ldd	Rd, Y+q	Rd is loaded with (Y + q)	`Rd = *(Y + q)`
	Register Z can also be used	Register X cannot be used.	q has to be between 0 and 63
lds	Rd, k	Load Rd with data in position k in memory.	`Rd = *k`

st	X, Rr	Store Rr in (X)	`*X = Rr`
	X+, Rd	Store Rr in (X), X is incremented	`*X = Rr, X++`
	-X, Rd	X is decremented, Store Rr in ( X )	`X--, *X = Rr`
	All three registers can be used
std	Y+q, Rr	stores Rr	`*(Y + q) = Rr`
	Register Z can also be used.	Register X cannot be used.	q has to be between 0 and 63
sts	k, Rr	Store Rr in position k in memory.	`*(k) = Rr`

push	Rr	Push Rr to stack	`SP--, *SP = Rr`
pop	Rd	Pop Rd from stack	`Rd = *SP, SP++`

Instruction	Operands	Description	Operation
add	Rd, Rr	Add Rr to Rd	`Rd += Rr`
sub	Rd, Rr	Subtract Rr from Rd	`Rd -= Rr`
subi	Rd, K	Subtract K from Rd	`Rd -= k`

inc	Rd	Increment Rd	`Rd++`
dec	Rd	Decrement Rd	`Rd--`
neg	Rd	Change sign of Rd	`Rd = -Rd`
mul	Rd, Rr	Unsigned multiply	`R1:R0 = Rd * Rr`

Instruction	Operands	Description	Operation
and	Rd, Rr	Conjunction of Rd and Rr	`Rd = Rd & Rr`
or	Rd, Rr	Disjunction of Rd and Rr	`Rd = Rd \| Rr`
eor	Rd, Rr	exclusive or of Rd and Rr	`Rd = Rd ^ Rr`
lsl/lsr	Rd	Shift left/right	Shift into C flag
rol/ror	Rd	Rotate left/right	Rotate with C flag
asr	Rd	Arithmetic shift right	Sign extended shift

Instruction	Operands	Description	Operation
cp	Rd, Rr	Subtract and update flags	`RD - Rr`
cpi	Rd, K	Subtract K and update flags	`Rd - K`
	Rd must be from R16 to R31	K must be between 0 and 255

Mnemonic	Operands	Description	Operation
jmp	k	unconditional jump
breq/brne	k	Branch if equal/ not equal	If `Z=1` (or `Z=0`) then `PC = PC + k + 1` otherwise `PC += 1`

brsh/brlo	k	Branch if same or higher/lower (unsigned)	If `C=1` (or `C=0`) then `PC = PC + k + 1` otherwise `PC += 1`

brge/brlt	k	Branch if greater or equal/lower (signed)	If `S=1` (or `S=0`) then `PC = PC + k + 1` otherwise `PC += 1`

Mnemonic	Operands	Description	Operation
call	k	Call subroutine in position k	`PC = k, SP -= 2, *SP = PC + 2`
ret		Return	`PC = *SP, SP += 2`

Mnemonic	Operands	Description	Operation
in	Rd, A	Load I/O data from address A to register Rd	`Rd = I/O[A]`
out	A, Rd	Store value in register Rd in I/O address A	`I/O[A] = Rd`