Gameboy Instruction Set

Home CPU Memory Routines

Instruction Map

Diadic Math Operations

Add Y+ℂ to X, store in X

📄️				📦️			📬️		✉️			𝟘	ℕ	ℍ	ℂ	⏱️
adc	A,	(HL)		8E			A	+=	HL	+ℂ		R	0	R	R	2
adc	A,	$kk		CE	kk		A	+=	kk	+ℂ		R	0	R	R	2
adc	A,	A		8F			A	+=	A	+ℂ		R	0	R	R	1
adc	A,	B		88			A	+=	B	+ℂ		R	0	R	R	1
adc	A,	C		89			A	+=	C	+ℂ		R	0	R	R	1
adc	A,	D		8A			A	+=	D	+ℂ		R	0	R	R	1
adc	A,	E		8B			A	+=	E	+ℂ		R	0	R	R	1
adc	A,	H		8C			A	+=	H	+ℂ		R	0	R	R	1
adc	A,	L		8D			A	+=	L	+ℂ		R	0	R	R	1

Add Y to X, store in X

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
add	A,	(HL)		86			A	+=	HL		R	0	R	R	2
add	A,	$kk		C6	kk		A	+=	kk		R	0	R	R	2
add	A,	A		87			A	+=	A		R	0	R	R	1
add	A,	B		80			A	+=	B		R	0	R	R	1
add	A,	C		81			A	+=	C		R	0	R	R	1
add	A,	D		82			A	+=	D		R	0	R	R	1
add	A,	E		83			A	+=	E		R	0	R	R	1
add	A,	H		84			A	+=	H		R	0	R	R	1
add	A,	L		85			A	+=	L		R	0	R	R	1

Substract Y+ℂ from X, store in X

📄️				📦️			📬️		✉️			𝟘	ℕ	ℍ	ℂ	⏱️
sbc	A,	(HL)		9E			A	-=	HL	+ℂ		R	1	R	R	2
sbc	A,	$kk		DE	kk		A	-=	kk	+ℂ		R	1	R	R	2
sbc	A,	A		9F			A	-=	A	+ℂ		R	1	R	R	1
sbc	A,	B		98			A	-=	B	+ℂ		R	1	R	R	1
sbc	A,	C		99			A	-=	C	+ℂ		R	1	R	R	1
sbc	A,	D		9A			A	-=	D	+ℂ		R	1	R	R	1
sbc	A,	E		9B			A	-=	E	+ℂ		R	1	R	R	1
sbc	A,	H		9C			A	-=	H	+ℂ		R	1	R	R	1
sbc	A,	L		9D			A	-=	L	+ℂ		R	1	R	R	1

Substract Y from X, store in X

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
sub	A,	(HL)		76			A	-=	HL		R	1	R	R	2
sub	A,	$kk		D6	kk		A	-=	kk		R	1	R	R	2
sub	A,	A		77			A	-=	A		R	1	R	R	1
sub	A,	B		70			A	-=	B		R	1	R	R	1
sub	A,	C		71			A	-=	C		R	1	R	R	1
sub	A,	D		72			A	-=	D		R	1	R	R	1
sub	A,	E		73			A	-=	E		R	1	R	R	1
sub	A,	H		74			A	-=	H		R	1	R	R	1
sub	A,	L		75			A	-=	L		R	1	R	R	1

Logical AND Y with X, store in X

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
and	A,	(HL)		A6			A	&=	HL		R	0	1	0	2
and	A,	$kk		E6	kk		A	&=	kk		R	0	1	0	2
and	A,	A		A7			A	&=	A		R	0	1	0	1
and	A,	B		A0			A	&=	B		R	0	1	0	1
and	A,	C		A1			A	&=	C		R	0	1	0	1
and	A,	D		A2			A	&=	D		R	0	1	0	1
and	A,	E		A3			A	&=	E		R	0	1	0	1
and	A,	H		A4			A	&=	H		R	0	1	0	1
and	A,	L		A5			A	&=	L		R	0	1	0	1

Inclusive OR Y with X, store in X

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
or	A,	(HL)		B6			A	|=	HL		R	0	0	0	2
or	A,	$kk		F6	kk		A	|=	kk		R	0	0	0	2
or	A,	A		B7			A	|=	A		R	0	0	0	1
or	A,	B		B0			A	|=	B		R	0	0	0	1
or	A,	C		B1			A	|=	C		R	0	0	0	1
or	A,	D		B2			A	|=	D		R	0	0	0	1
or	A,	E		B3			A	|=	E		R	0	0	0	1
or	A,	H		B4			A	|=	H		R	0	0	0	1
or	A,	L		B5			A	|=	L		R	0	0	0	1

Exclusive OR Y with X, store in X

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
xor	A,	(HL)		AE			A	^=	HL		R	0	0	0	2
xor	A,	$kk		EE	kk		A	^=	kk		R	0	0	0	2
xor	A,	A		AF			A	^=	A		R	0	0	0	1
xor	A,	B		A8			A	^=	B		R	0	0	0	1
xor	A,	C		A9			A	^=	C		R	0	0	0	1
xor	A,	D		AA			A	^=	D		R	0	0	0	1
xor	A,	E		AB			A	^=	E		R	0	0	0	1
xor	A,	H		AC			A	^=	H		R	0	0	0	1
xor	A,	L		AD			A	^=	L		R	0	0	0	1

Compare Y and X

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
cp	A,	(HL)		BE			A	==	HL		R	1	R	R	2
cp	A,	$kk		FE	kk		A	==	kk		R	1	R	R	2
cp	A,	A		BF			A	==	A		R	1	R	R	1
cp	A,	B		B8			A	==	B		R	1	R	R	1
cp	A,	C		B9			A	==	C		R	1	R	R	1
cp	A,	D		BA			A	==	D		R	1	R	R	1
cp	A,	E		BB			A	==	E		R	1	R	R	1
cp	A,	H		BC			A	==	H		R	1	R	R	1
cp	A,	L		BD			A	==	L		R	1	R	R	1

Monadic Math Operations

Increase X by 1

📄️			📦️			📬️			𝟘	ℕ	ℍ	ℂ	⏱️
inc	(HL)		34			HL	++		R	0	R		3
inc	BC		03			BC	++		R	0	R		2
inc	DE		13			DE	++		R	0	R		2
inc	HL		23			HL	++		R	0	R		2
inc	SP		33			SP	++		R	0	R		2
inc	A		3C			A	++		R	0	R		1
inc	B		04			B	++		R	0	R		1
inc	C		0C			C	++		R	0	R		1
inc	D		14			D	++		R	0	R		1
inc	E		1C			E	++		R	0	R		1
inc	H		24			H	++		R	0	R		1
inc	L		2C			L	++		R	0	R		1

Decrease X by 1

📄️			📦️			📬️			𝟘	ℕ	ℍ	ℂ	⏱️
dec	(HL)		35			HL	--		R	1	R		3
dec	BC		0B			BC	--		R	1	R		2
dec	DE		1B			DE	--		R	1	R		2
dec	HL		2B			HL	--		R	1	R		2
dec	SP		3B			SP	--		R	1	R		2
dec	A		3D			A	--		R	1	R		1
dec	B		05			B	--		R	1	R		1
dec	C		0D			C	--		R	1	R		1
dec	D		15			D	--		R	1	R		1
dec	E		1D			E	--		R	1	R		1
dec	H		25			H	--		R	1	R		1
dec	L		2D			L	--		R	1	R		1

Pop X from top of stack updating SP

📄️			📦️			📬️				𝟘	ℕ	ℍ	ℂ	⏱️
pop	AF		F1			AF	=	--SP						3
pop	BC		C1			BC	=	--SP						3
pop	DE		D1			DE	=	--SP						3
pop	HL		E1			HL	=	--SP						3

Push X onto top of stack updating SP

📄️			📦️			📬️				𝟘	ℕ	ℍ	ℂ	⏱️
push	AF		F5			SP++	=	AF						4
push	BC		C5			SP++	=	BC						4
push	DE		D5			SP++	=	DE						4
push	HL		E5			SP++	=	HL						4

Decimal adjust A (after add/sub of BCD data)

📄️		📦️			📬️			𝟘	ℕ	ℍ	ℂ	⏱️
daa		27			A	$=ℍ		R		0	R	1

Complement A (1's complement)

📄️		📦️			📬️			𝟘	ℕ	ℍ	ℂ	⏱️
cpl		2F			A	^=$FF			1	1		1

Set carry flag (to 1)

📄️		📦️			📬️			𝟘	ℕ	ℍ	ℂ	⏱️
scf		37			ℂ	=$1			0	0	1	1

Complement carry flag

📄️		📦️			📬️			𝟘	ℕ	ℍ	ℂ	⏱️
ccf		3F			ℂ	^=$1			0	0	R	1

Program Flow

Call subroutine at $aabb

📄️			📦️					📬️		📬️	✉️	⏱️
call		$aabb	CD	bb	aa			SP++	←	PC	←aabb	6
call	c,	$aabb	DC	bb	aa		ℂ?	SP++	←	PC	←aabb	6/3
call	nc,	$aabb	D4	bb	aa		ℂ!	SP++	←	PC	←aabb	6/3
call	z,	$aabb	C4	bb	aa		𝟘?	SP++	←	PC	←aabb	6/3
call	nz,	$aabb	CC	bb	aa		𝟘!	SP++	←	PC	←aabb	6/3

Jump to location at $aabb

📄️			📦️					📬️		✉️		⏱️
jp		$aabb	C3	bb	aa			PC	=	aabb		4
jp	c,	$aabb	DA	bb	aa		ℂ?	PC	=	aabb		4/3
jp	nc,	$aabb	D2	bb	aa		ℂ!	PC	=	aabb		4/3
jp	z,	$aabb	C2	bb	aa		𝟘?	PC	=	aabb		4/3
jp	nz,	$aabb	CA	bb	aa		𝟘!	PC	=	aabb		4/3
jp		(HL)	E9					PC	=	HL		1

Jump relative by X

📄️			📦️					📬️		✉️		⏱️
jr		$aabb	18	bb	aa			PC	=	aabb		3
jr	c,	$aabb	38	bb	aa		ℂ?	PC	+=	aabb		3/2
jr	nc,	$aabb	20	bb	aa		ℂ!	PC	+=	aabb		3/2
jr	z,	$aabb	20	bb	aa		𝟘?	PC	+=	aabb		3/2
jr	nz,	$aabb	28	bb	aa		𝟘!	PC	+=	aabb		3/2

Return from subroutine

📄️			📦️					📬️		✉️		⏱️
ret			C9					PC	=	--sp		4
ret	c		D8				ℂ?	PC	=	--sp		5/2
ret	nc		D0				ℂ!	PC	=	--sp		5/2
ret	nz		C0				𝟘?	PC	=	--sp		5/2
ret	z		C8				𝟘!	PC	=	--sp		5/2

Call picoroutine at x

📄️			📦️					📬️		✉️		⏱️
rst	$00		C7					PC	=	00		4
rst	$08		CF					PC	=	08		4
rst	$10		D7					PC	=	10		4
rst	$18		DF					PC	=	18		4
rst	$20		E7					PC	=	20		4
rst	$28		EF					PC	=	28		4
rst	$30		F7					PC	=	30		4
rst	$38		FF					PC	=	38		4

Return from interrupt

📄️		📦️						📬️		✉️		⏱️
reti		D9				𝕀=1;		PC	=	--sp		4

Disable Interrupts

📄️		📦️				📬️		✉️				⏱️
di		F3				𝕀	=	0				1

Enable Interrupts

📄️		📦️				📬️		✉️				⏱️
ei		FB				𝕀	=	1				1

Wait for interrupt or reset

📄️		📦️				📬️		✉️				⏱️
halt		76				PC	=	PC	-1			:-P

Stop CPU until P1-P10 go high

📄️		📦️
stop		10	00

8bit Load Commands

Load from X to register B

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	B,	B		40			B	=	B						4
ld	B,	C		41			B	=	C						4
ld	B,	D		42			B	=	D						4
ld	B,	E		43			B	=	E						4
ld	B,	H		44			B	=	H						4
ld	B,	L		45			B	=	L						4
ld	B,	(HL)		46			B	=	HL						8
ld	B,	A		47			B	=	A						4

Load from X to register C

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	C,	B		48			C	=	B						4
ld	C,	C		49			C	=	C						4
ld	C,	D		4A			C	=	D						4
ld	C,	E		4B			C	=	E						4
ld	C,	H		4C			C	=	H						4
ld	C,	L		4D			C	=	L						4
ld	C,	(HL)		4E			C	=	HL						8
ld	C,	A		4F			C	=	A						4

Load from X to register D

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	D,	B		50			D	=	B						4
ld	D,	C		51			D	=	C						4
ld	D,	D		52			D	=	D						4
ld	D,	E		53			D	=	E						4
ld	D,	H		54			D	=	H						4
ld	D,	L		55			D	=	L						4
ld	D,	(HL)		56			D	=	HL						8
ld	D,	A		57			D	=	A						4

Load from X to register E

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	E,	B		58			E	=	B						4
ld	E,	C		59			E	=	C						4
ld	E,	D		5A			E	=	D						4
ld	E,	E		5B			E	=	E						4
ld	E,	H		5C			E	=	H						4
ld	E,	L		5D			E	=	L						4
ld	E,	(HL)		5E			E	=	HL						8
ld	E,	A		5F			E	=	A						4

Load from X to register H

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	H,	B		60			H	=	B						4
ld	H,	C		61			H	=	C						4
ld	H,	D		62			H	=	D						4
ld	H,	E		63			H	=	E						4
ld	H,	H		64			H	=	H						4
ld	H,	L		65			H	=	L						4
ld	H,	(HL)		66			H	=	HL						8
ld	H,	A		67			H	=	A						4

Load from X to register L

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	L,	B		68			L	=	B						4
ld	L,	C		69			L	=	C						4
ld	L,	D		6A			L	=	D						4
ld	L,	E		6B			L	=	E						4
ld	L,	H		6C			L	=	H						4
ld	L,	L		6D			L	=	L						4
ld	L,	(HL)		6E			L	=	HL						8
ld	L,	A		6F			L	=	A						4

Load from X to address in (HL)

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	(HL),	B		70			HL	=	B						8
ld	(HL),	C		71			HL	=	C						8
ld	(HL),	D		72			HL	=	D						8
ld	(HL),	E		73			HL	=	E						8
ld	(HL),	H		74			HL	=	H						8
ld	(HL),	L		75			HL	=	L						8
ld	(HL),	A		77			HL	=	A						8

Load from X to register A

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	A,	B		78			A	=	B						4
ld	A,	C		79			A	=	C						4
ld	A,	D		7A			A	=	D						4
ld	A,	E		7B			A	=	E						4
ld	A,	H		7C			A	=	H						4
ld	A,	L		7D			A	=	L						4
ld	A,	(HL)		7E			A	=	HL						8
ld	A,	A		7F			A	=	A						4

Load constant kk to register X

📄️				📦️				📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	B,	$kk		06	kk			B	=	kk						8
ld	C,	$kk		0E	kk			C	=	kk						8
ld	D,	$kk		16	kk			D	=	kk						8
ld	E,	$kk		1E	kk			E	=	kk						8
ld	H,	$kk		26	kk			H	=	kk						8
ld	L,	$kk		2E	kk			L	=	kk						8
ld	(HL),	$kk		36	kk			HL	=	kk						12
ld	A,	$kk		3E	kk			A	=	kk						8

Load from address to register A

📄️				📦️					📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	A,	(BC)		0A					A	=	BC						8
ld	A,	(DE)		1A					A	=	DE						8
ld	A,	(kk)		FA	kk	kk			A	=	kk						16

Load from register A to address

📄️				📦️					📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	(BC),	A		02					BC	=	A						8
ld	(DE),	A		12					DE	=	A						8
ld	(kk),	A		EA	kk	kk			kk	=	A						16

Read from IO-port to register A

📄️				📦️				📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	A,	FFkk		F0	kk			A	=	FFkk						12
ld	A,	FF00+C		F2				A	=	FF00+C						8

Write register A to IO-port

📄️				📦️				📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	FFkk,	A		E0	kk			FFkk	=	A						12
ld	FF00+C,	A		E2				FF00+C	=	A						8

Load Incremental from A to (HL)

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ldi	(HL),	A		22			HL++	=	A						8
ldd	(HL),	A		32			HL--	=	A						8

Load Incremental from (HL) to A

📄️				📦️		📬️		✉️			𝟘	ℕ	ℍ	ℂ	⏱️
ldi	A,	(HL)		2A			A	=	HL++						8
ldd	A,	(HL)		3A			A	=	HL--						8

16bit Load Commands

Load 16bit constant to register

📄️				📦️					📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	BC,	kkkk		01	kk	kk			BC	=	kkkk						12
ld	DE,	kkkk		11	kk	kk			DE	=	kkkk						12
ld	HL,	kkkk		21	kk	kk			HL	=	kkkk						12
ld	SP,	kkkk		31	kk	kk			SP	=	kkkk						12

Load from HL to SP

📄️				📦️			📬️		✉️		𝟘	ℕ	ℍ	ℂ	⏱️
ld	SP,	HL		F9			SP	=	HL						8

Rotate & Shift Operations

Bit Operations