Zilog Z80 Assembler Syntax

Zilog Z80 CPU Assembler Syntax

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ASM: Is the assembler source code.
OBJ: Is the object code (binary executable).

Select the Mnemonic you want detailed info about:

Mnemonic:	Description:
ADC	ADD WITH CARRY
ADD	ADD
AND	LOGICAL AND
BIT	BIT TEST
CALL	CALL SUB ROUTINE
CCF	COMPLEMENT CARRY FLAG
CP	COMPARE
CPD	COMPARE AND DECREMENT
CPDR	COMPARE DECREMENT AND REPEAT
CPI	COMPARE AND INCREMENT
CPIR	COMPARE INCREMENT AND REPEAT
CPL	COMPLEMENT ACCUMULATOR
DAA	DECIMAL ADJUST ACCUMULATOR
DEC	DECREMENT
DI	DISABLE INTERRUPTS
DJNZ	DEC JUMP NON-ZERO
EI	ENABLE INTERRUPTS
EX	EXCHANGE REGISTER PAIR
EXX	EXCHANGE ALTERNATE REGISTERS
HALT	HALT, WAIT FOR INTERRUPT OR RESET
IM	INTERRUPT MODE 0 1 2
IN	INPUT FROM PORT
INC	INCREMENT
IND	INPUT, DEC HL, DEC B
INDR	INPUT, DEC HL, DEC B, REPEAT IF B>0
INI	INPUT, INC HL, DEC B
INIR	INPUT, INC HL, DEC B, REPEAT IF B>0
JP	JUMP
JR	JUMP RELATIVE
LD	LOAD DATA TO/FROM REGISTERS/MEMORY
LDD	LOAD DECREMENT
LDDR	LOAD DECREMENT AND REPEAT
LDI	LOAD AND INCREMENT
LDIR	LOAD INCREMENT AND REPEAT
NEG	NEGATE ACCUMULATOR 2'S COMPLEMENT
NOP	NO OPERATION
OR	--
OTDR	OUTPUT, DEC HL, DEC B, REPEAT IF B>0
OTIR	OUTPUT, INC HL, DEC B, REPEAT IF B>0
OUT	OUTPUT TO PORT
OUTD	OUTPUT, DEC HL, DEC B
OUTI	OUTPUT, INC HL, DEC B
POP	POP FROM STACK
PUSH	PUSH INTO STACK
RES	RESET BIT
RET	RETURN FROM SUB ROUTINE
RETI	RETURN FROM INTERRUPT
RETN	RETURN FROM NON MASKABEL INTERRUPT
RL	ROTATE LEFT register
RLA	ROTATE LEFT ACUMULATOR
RLC	ROTATE LEFT THROUGH CARRY register
RLCA	ROTATE LEFT THROUGH CARRY ACCUMULATUR
RLD	ROTATE LEFT DIGIT
RR	ROTATE RIGHT register
RRA	ROTATE RIGHT ACCUMULATOR
RRC	ROTATE RIGHT CIRCULAR register
RRCA	ROTATE RIGHT CIRCULAR ACCUMULATOR
RRD	ROTATE RIGHT DIGIT
RST	RESTART
SBC	SUBTRACT WITH CARRY
SCF	SET CARRY FLAG
SET	SET BIT
SLA	SHIFT LEFT ARITHMETIC register
SRA	SHIFT RIGHT ARITHMETIC register
SRL	SHIFT RIGHT LOGICAL register
SUB	SUBTRACTION
XOR	EXCLUSIVE OR

Detailed info ADC

ADD WITH CARRY

Detailed info ADD

Detailed info AND

LOGICAL AND

Detailed info BIT

BIT TEST

Detailed info CALL

CALL a subroutine

Detailed info CCF

Opperation: CY = Inv CY

Instruction Format:

Opcode: CCF
OBJ: 3Fh

Description:

The Carry flag in the flags register is inverted.

H: Pprevious carry will be copied to H.

P/V: Not affected.

N: Reset.

C: Set if carry was 0 before operation, reset otherwise.

Detailed info CP

COMPARE

Detailed info CPD

COMPARE AND DECREMENT

Detailed info CPDR

COMPARE DECREMENT AND REPEAT

Flags: CY Z PV S N H . ~ ~ ~ 1 ~ (~ = changes, . = no change) And the flags: if byte found: Z=1; HL - address of next byte; BC - figure out by yourself. not found: Z=0

Detailed info CPI

COMPARE AND INCREMENT

Detailed info CPIR

COMPARE INCREMENT AND REPEAT




Flags: CY Z  PV S  N  H 
       .  ~  ~  ~  1  ~ (~ = changes, . = no change)

And the flags: if byte found: Z=1; HL - address of next byte;
                                   BC - figure out by yourself.
                   not found: Z=0
I believe, that if on exit BC=0 then PV=0 else PV=1, that's so with CPI
(CPD) command, so why shouldn't it be with CPIR (CPDR)?

So the difference between if a byte, is or is not found, is expressed
by the Zero flag. Sorry, don't know exactly how are S and H affected...

Detailed info CPL

COMPLEMENT ACCUMULATOR

Detailed info DAA

Instruction Format:

OPCODE                    CYCLES
--------------------------------
  27h                       4


Description:
This instruction conditionally adjusts the accumulator for BCD addition
and subtraction operations. For addition (ADD, ADC, INC) or subtraction
(SUB, SBC, DEC, NEC), the following table indicates the operation performed:

--------------------------------------------------------------------------------
|           | C Flag  | HEX value in | H Flag | HEX value in | Number  | C flag|
| Operation | Before  | upper digit  | Before | lower digit  | added   | After |
|           | DAA     | (bit 7-4)    | DAA    | (bit 3-0)    | to byte | DAA   |
|------------------------------------------------------------------------------|
|           |    0    |     0-9      |   0    |     0-9      |   00    |   0   |
|   ADD     |    0    |     0-8      |   0    |     A-F      |   06    |   0   |
|           |    0    |     0-9      |   1    |     0-3      |   06    |   0   |
|   ADC     |    0    |     A-F      |   0    |     0-9      |   60    |   1   |
|           |    0    |     9-F      |   0    |     A-F      |   66    |   1   |
|   INC     |    0    |     A-F      |   1    |     0-3      |   66    |   1   |
|           |    1    |     0-2      |   0    |     0-9      |   60    |   1   |
|           |    1    |     0-2      |   0    |     A-F      |   66    |   1   |
|           |    1    |     0-3      |   1    |     0-3      |   66    |   1   |
|------------------------------------------------------------------------------|
|   SUB     |    0    |     0-9      |   0    |     0-9      |   00    |   0   |
|   SBC     |    0    |     0-8      |   1    |     6-F      |   FA    |   0   |
|   DEC     |    1    |     7-F      |   0    |     0-9      |   A0    |   1   |
|   NEG     |    1    |     6-F      |   1    |     6-F      |   9A    |   1   |
|------------------------------------------------------------------------------|

Flags:

C: See instruction.

N: Unaffected.

P/V: Set if Acc. is even parity after operation, reset otherwise.

H: See instruction.

Z: Set if Acc. is Zero after operation, reset otherwise.

S: Set if most significant bit of Acc. is 1 after operation, reset otherwise.


Example:

If an addition operation is performed between 15 (BCD) and 27 (BCD), simple decimal
arithmetic gives this result:

    15
   +27
   ----
    42

But when the binary representations are added in the Accumulator according to
standard binary arithmetic:

   0001 0101  15
  +0010 0111  27
  ---------------
   0011 1100  3C

The sum is ambiguous. The DAA instruction adjusts this result so that correct
BCD representation is obtained:

   0011 1100  3C result
  +0000 0110  06 +error
  ---------------
   0100 0010  42 Correct BCD!

Detailed info DEC

DECREMENT

Detailed info DI

DISABLE INTERRUPTS

Detailed info DJNZ

DEC JUMP NON-ZERO

Detailed info EI

ENABLE INTERRUPTS

Detailed info EX

EXCHANGE REGISTER PAIR


ASM: EX  DE,HL
OBJ: EBh
Tstates : 4.

ASM: EX  AF,AF'
OBJ: 08h
Tstates : 4.


Description:
The 16bit value in the two registers are exchanged.
note: register pair AF consists of register A and the flags register F


ASM: EX  (SP),HL
OBJ: E3h
Tstates : 19.


Description:
The low order byte contained in register pait HL is exchanged with the contents
of the memory address spefified by the contents of register pair SP (Stack Pointer),
and the high order byte of HL is exchanges with the next highest memory address (SP+1).
H <-> (SP+1) , L <-> (SP)  this will not affect the contents of SP.


ASM: EX  (SP),IX
OBJ: DDh, E3h
Tstates : 23.



ASM: EX  (SP),IY
OBJ: FDh, E3h
Tstates : 23.


Description:
Does the same as above.
eg:  IXH <-> (SP+1), IXL <-> (SP)  IXH = IX height byte, IXL = IX low byte..

Detailed info EXX

EXCHANGE ALTERNATE REGISTERS


ASM: EXX
OBJ: D9h
Tstates : 4.

Description:
Each 16bit value in register pairs BC, DE, HL is exchanged with the 16bit value in BC', DE', HL' respectively.
eg:
BC <-> BC'
DE <-> DE'
HL <-> HL'

Detailed info HALT

HALT, WAIT FOR INTERRUPT OR RESET


ASM: HALT
OBJ: 76h
Tstates : 4.

Description:
The HALT instruction suspends CPU operation until a interrupt or reset is received.
While in the halted state, the processor will execute NOP's to maintain memory refresh logic.

Detailed info IM

INTERRUPT MODE 0 1 2

Detailed info IN

INPUT FROM PORT

Detailed info INC

INCREMENT

Detailed info IND

Instruction Format:

OPCODE        CYCLES
-------------------------------
 ED  AA         16 

Description:
The contents of register C are placed on the bottom half (A0-A7) of the address
bus to select the I/O device. Register B may be used as a byte counter, and its
contents are placed on the top half (A8-A15) af the address bus at this time.
Then one byte from the selected port is placed on the data bus and written to the
CPU. The contents of the HL register pair are pointer to store the redden byte
in memory. The register pair HL is decremented, the byte counter B is decremented.

Flags:

Z: Set if B-1=0, reset otherwise.

S: UnKnown.


Example:

Reg C=07h
Reg B=10h
Reg HL=1000h
IO port nr. 07h contain data 7Bh

Then after the execution of
IND
The HL register pair will contain 0FFFh, and register B will contain 0Fh,
and memory location 1000h will contain 7Bh.

Detailed info INDR

Instruction Format:

OPCODE                   CYCLES
--------------------------------------------
 ED  BA         16 if B=0    21 if B >< 0

Description:
The contents of register C are placed on the bottom half (A0-A7) of the address
bus to select the I/O device. Register B is used as a byte counter, and its
contents are placed on the top half (A8-A15) af the address bus at this time.
Then one byte from the selected port is placed on the data bus and written to the
CPU. The contents of the HL register pair are pointer to store the redden byte
in memory. The register pair HL is decremented, the byte counter B is decremented.
If decrementing causes B to go to zero, the instruction is terminated. If B is not
zero, the instruction is repeated.

Flags:


Example:

Reg C=07h
Reg B=03h
Reg HL=1000h
IO port nr. 07h contain data 51h, A9h, 03h

Then after the execution of
INDR
The HL register pair will contain 0FFDh, and register B will contain zero,
and memory locations will have contents as follows:

Location:    Contents:
0FFEh        03h
0FFFh        A9h
1000h        51h

Detailed info INI

Instruction Format:

OPCODE        CYCLES
---------------------
 ED  A2         16


Description:
The contents of register C are placed on the bottom half (A0-A7) of the address
bus to select the I/O device. Register B may be used as a byte counter, and its
contents are placed on the top half (A8-A15) af the address bus at this time.
Then one byte from the selected port is placed on the data bus and written to the
CPU. The contents of the HL register pair are pointer to store the redden byte
in memory. Finally the byte counter B is decremented and register pair HL is incremented.

Flags:

Z: Set if B-1=0, reset otherwise.

S: UnKnown.


Example:

Reg C=07h
Reg B=12h
Reg HL=1000h
IO port nr. 07h contain data 7Bh

Then after the execution of
INI
Memory location 1000h will contain 7Bh, the HL register pair will contain
1001h, and register B will contain 11h.

Detailed info INIR

Instruction Format:

OPCODE                   CYCLES
--------------------------------------------
 ED  B2         16 if B=0    21 if B >< 0

Description:
The contents of register C are placed on the bottom half (A0-A7) of the address
bus to select the I/O device. Register B is used as a byte counter, and its
contents are placed on the top half (A8-A15) af the address bus at this time.
Then one byte from the selected port is placed on the data bus and written to the
CPU. The contents of the HL register pair are pointer to store the redden byte
in memory. The register pair HL is incremented, the byte counter B is decremented.
If decrementing causes B to go to zero, the instruction is terminated. If B is not
zero, the instruction is repeated.

Flags:


Example:

Reg C=07h
Reg B=03h
Reg HL=1000h
IO port nr. 07h contain data 51h, A9h, 03h

Then after the execution of
INIR
The HL register pair will contain 1003h, and register B will contain zero,
and memory locations will have contents as follows:

Location:    Contents:
1000h        51h
1001h        A9h
1002h        03h

Detailed info JP

JUMP to address.

Detailed info JR

JUMP to address, Relative

Detailed info LD

Instruction Format:

OPCODE  r    r'                             CYCLES
----------------------------------------------------
  01   ddd  sss     LD   r,r'    dst,src      4


Introductory note -- Binary form of opcodes

  Example:   LD r,r'
 
The 8-bit binary opcode is

        r  r'
     01dddsss
 
   ...where "ddd" is a three-bit field specifying the destination,
  and "sss" is a three-bit field specifying the source.
 
the value for ddd and sss is shown below:

Registers
--------------
 A = 111
 B = 000
 C = 001
 D = 010
 E = 011
 H = 100
 L = 101

Operation: dst <-- src

The contest of the source operand are loaded into the destination operand. The contents of the source operand are not affected.

Flags:

Example: If register E, contains the value 10h, The statement:

ASM: LD H,E
OBJ: 63h

Loads the value 10H into register H.

Detailed info LDD

Instruction Format:

OPCODE          CYCLES
-----------------------------
 ED  A8           16 

Description:
This instruction transfers a byte of data from memory location addressed
by the register pair HL, to the memory location addressed by the register pair DE.
Then both af these register pairs including the BC (byte counter) register pair
are decremented.

Flags:

C: Not affected.

N: reset.

P/V: Set if BC-1 is not 0, reset otherwise.

H: Reset.

Z: Not affected.

S: Not affected.

Detailed info LDDR

Instruction Format:

OPCODE          CYCLES
-----------------------------
 ED  A8           16 

Description:
This instruction transfers a byte of data from memory location addressed
by the register pair HL, to the memory location addressed by the register pair DE.
Then both af these register pairs including the BC (byte counter) register pair
are decremented.

Flags:

C: Not affected.

N: reset.

P/V: Set if BC-1 is not 0, reset otherwise.

H: Reset.

Z: Not affected.

S: Not affected.

Detailed info LDI

LOAD AND INCREMENT

Detailed info LDIR

LOAD INCREMENT AND REPEAT

Detailed info NEG

NEGATE ACCUMULATOR 2'S COMPLEMENT

Detailed info NOP

NO OPERATION, not the most complicated instruction :-)

Detailed info OR

Detailed info OTDR

OUTPUT, DEC HL, DEC B, REPEAT IF B>0

Detailed info OTIR

OUTPUT, INC HL, DEC B, REPEAT IF B>0

Detailed info OUT

OUTPUT TO PORT

Detailed info OUTD

OUTPUT, DEC HL, DEC B

Detailed info OUTI

OUTPUT, INC HL, DEC B

Detailed info POP

POP FROM STACK

Detailed info PUSH

PUSH INTO STACK

Detailed info RES

RESET BIT

Detailed info RET

RETURN FROM SUB ROUTINE

Detailed info RETI

RETURN FROM INTERRUPT

Detailed info RETN

RETURN FROM NON MASKABEL INTERRUPT

Detailed info RL

Instruction Format:

ASM: RL B
OBJ: CBh, 10h
Tstates : 8.

ASM: RL C
OBJ: CBh, 11h
Tstates : 8.

ASM: RL D
OBJ: CBh, 12h
Tstates : 8.

ASM: RL E
OBJ: CBh, 13h
Tstates : 8.

ASM: RL H
OBJ: CBh, 14h
Tstates : 8.

ASM: RL L
OBJ: CBh, 15h
Tstates : 8.

ASM: RL A
OBJ: CBh, 17h
Tstates : 8.

ASM: RL (HL)
OBJ: CBh, 16h
Tstates : 15.

ASM: RL (IX+D)
OBJ: DDh, CBh, XX, 16h
Tstates : 23.

ASM: RL (IY+D)
OBJ: FDh, CBh, XX, 16h
Tstates : 23.

XX is the offset value.

Detailed info RLA

Instruction Format:

ASM: RLA
OBJ: 17h
Tstates : 4.

Detailed info RLC

Instruction Format:

ASM: RLC B
OBJ: CBh, 00h
Tstates : 8.

ASM: RLC C
OBJ: CBh, 01h
Tstates : 8.

ASM: RLC D
OBJ: CBh, 02h
Tstates : 8.

ASM: RLC E
OBJ: CBh, 03h
Tstates : 8.

ASM: RLC H
OBJ: CBh, 04h
Tstates : 8.

ASM: RLC L
OBJ: CBh, 05h
Tstates : 8.

ASM: RLC A
OBJ: CBh, 07h
Tstates : 8.

ASM: RLC (HL)
OBJ: CBh, 06h
Tstates : 15.

ASM: RLC (IX+D)
OBJ: DDh, CBh, XX, 06h
Tstates : 23.

ASM: RLC (IY+D)
OBJ: FDh, CBh, XX, 06h
Tstates : 23.

XX is the offset value.

Detailed info RLCA

Instruction Format:

ASM: RLCA
OBJ: 07h
Tstates : 4.

Detailed info RLD

Instruction Format:

ASM: RLD
OBJ: EDh, 6Fh
Tstates : 18.

Detailed info RR

Instruction Format:

ASM: RR B
OBJ: CBh, 18h
Tstates : 8.

ASM: RR C
OBJ: CBh, 19h
Tstates : 8.

ASM: RR D
OBJ: CBh, 1Ah
Tstates : 8.

ASM: RR E
OBJ: CBh, 1Bh
Tstates : 8.

ASM: RR H
OBJ: CBh, 1Ch
Tstates : 8.

ASM: RR L
OBJ: CBh, 1Dh
Tstates : 8.

ASM: RR A
OBJ: CBh, 1Fh
Tstates : 8.

ASM: RR (HL)
OBJ: CBh, 1Eh
Tstates : 15.

ASM: RR (IX+D)
OBJ: DDh, CBh, XX, 1Eh
Tstates : 23.

ASM: RR (IY+D)
OBJ: FDh, CBh, XX, 1Eh
Tstates : 23.

XX is the offset value.

Detailed info RRA

Instruction Format:

ASM: RRA
OBJ: 1Fh
Tstates : 4.

Detailed info RRC

Instruction Format:

ASM: RRC B
OBJ: CBh, 08h
Tstates : 8.

ASM: RRC C
OBJ: CBh, 09h
Tstates : 8.

ASM: RRC D
OBJ: CBh, 0Ah
Tstates : 8.

ASM: RRC E
OBJ: CBh, 0Bh
Tstates : 8.

ASM: RRC H
OBJ: CBh, 0Ch
Tstates : 8.

ASM: RRC L
OBJ: CBh, 0Dh
Tstates : 8.

ASM: RRC A
OBJ: CBh, 0Fh
Tstates : 8.

ASM: RRC (HL)
OBJ: CBh, 0Eh
Tstates : 15.

ASM: RRC (IX+D)
OBJ: DDh, CBh, XX, 0Eh
Tstates : 23.

ASM: RRC (IY+D)
OBJ: FDh, CBh, XX, 0Eh
Tstates : 23.

XX is the offset value.

Detailed info RRCA

Instruction Format:

ASM: RRCA
OBJ: 0Fh
Tstates : 4.

Detailed info RRD

Instruction Format:

ROTATE RIGHT DIGIT

ASM: RRD
OBJ: EDh, 67h
Tstates : 18.

Detailed info RST

Instruction Format:

OPCODE   CALL ADDRESS   MNEMONIC    CYCLES
----------------------------------------------------
  C7h    0000h          RST 0
  CFh    0008h          RST 8
  D7h    0010h          RST 16
  DFh    0018h          RST 24
  E7h    0020h          RST 32
  EFh    0028h          RST 40
  F7h    0030h          RST 48
  FFh    0038h          RST 56

Detailed info SBC

SUBTRACT WITH CARRY

Detailed info SCF

The Carry flag in the flags register is set (1).

Detailed info SET b, r

Operation: rb = 1
Instruction Format:

CBh

Bit b in register r is set. Operands b and r are specified as follows:

Bit   b        Register   r
 0   000          B      000
 1   001          C      001
 2   010          D      010 
 3   011          E      011
 4   100          H      100 
 5   101          L      101
 6   110          A      111
 7   111

Tstates: 8.
Flags: None Affected

Example:
ASM: SET 3,D
OBJ: CBh, DAh

Detailed info SET b, (HL)

Operation: (HL)b = 1
Instruction Format:

CBh

Bit b in the memory location addressed by the contents of register pair HL is set. Operands b is specified as follows:

Tstates: 15.
Flags: None Affected

Example:
ASM: SET 5,(HL)
OBJ: CBh, EEh

Detailed info SET b, (IX+d)

Operation: (IX+d)b = 1
Instruction Format:

DDh
CBh

Bit b is set, in the memory location addressed by the sum of the contents of register IX and the two's complement integer d. (d = adr. offset)
Operands b is specified as follows:

Tstates: 23.
Flags: None Affected

Example:
ASM: SET 0,(IX+3h)
OBJ: DDh, CBh, 03h, C6h

If the contents of index Register IX are 2000h, then bit 0 in memory location 2003h will be 1 (set).
Bit 0 is the least significant bit)

Detailed info SET b, (IY+d)

Operation: (IY+d)b = 1
Instruction Format:

FDh
CBh

Bit b is set, in the memory location addressed by the sum of the contents of register IY and the two's complement integer d. (d = adr. offset)
Operands b is specified as follows:

Tstates: 23.
Flags: None Affected

Example:
ASM: SET 0,(IY+47h)
OBJ: DDh, CBh, 47h, C6h

If the contents of index Register IX are 2000h, then bit 0 in memory location 2047h will be 1 (set).
Bit 0 is the least significant bit)

Detailed info SLA

Instruction Format:

ASM: SLA B
OBJ: CBh, 20h
Tstates : 8.

ASM: SLA C
OBJ: CBh, 21h
Tstates : 8.

ASM: SLA D
OBJ: CBh, 22h
Tstates : 8.

ASM: SLA E
OBJ: CBh, 23h
Tstates : 8.

ASM: SLA H
OBJ: CBh, 24h
Tstates : 8.

ASM: SLA L
OBJ: CBh, 25h
Tstates : 8.

ASM: SLA A
OBJ: CBh, 27h
Tstates : 8.

ASM: SLA (HL)
OBJ: CBh, 26h
Tstates : 15.

ASM: SLA (IX+D)
OBJ: DDh, CBh, XX, 26h
Tstates : 23.

ASM: SLA (IY+D)
OBJ: FDh, CBh, XX, 26h
Tstates : 23.

XX is the offset value.

Detailed info SRA

Instruction Format:

ASM: SRA B
OBJ: CBh, 28h
Tstates : 8.

ASM: SRA C
OBJ: CBh, 29h
Tstates : 8.

ASM: SRA D
OBJ: CBh, 2Ah
Tstates : 8.

ASM: SRA E
OBJ: CBh, 2Bh
Tstates : 8.

ASM: SRA H
OBJ: CBh, 2Ch
Tstates : 8.

ASM: SRA L
OBJ: CBh, 2Dh
Tstates : 8.

ASM: SRA A
OBJ: CBh, 2Fh
Tstates : 8.

ASM: SRA (HL)
OBJ: CBh, 2Eh
Tstates : 15.

ASM: SRA (IX+D)
OBJ: DDh, CBh, XX, 2Eh
Tstates : 23.

ASM: SRA (IY+D)
OBJ: FDh, CBh, XX, 2Eh
Tstates : 23.

XX is the offset value.

Detailed info SRL

Instruction Format:

ASM: SRL B
OBJ: CBh, 38h
Tstates : 8.

ASM: SRL C
OBJ: CBh, 39h
Tstates : 8.

ASM: SRL D
OBJ: CBh, 3Ah
Tstates : 8.

ASM: SRL E
OBJ: CBh, 3Bh
Tstates : 8.

ASM: SRL H
OBJ: CBh, 3Ch
Tstates : 8.

ASM: SRL L
OBJ: CBh, 3Dh
Tstates : 8.

ASM: SRL A
OBJ: CBh, 3Fh
Tstates : 8.

ASM: SRL (HL)
OBJ: CBh, 3Eh
Tstates : 15.

ASM: SRL (IX+D)
OBJ: DDh, CBh, XX, 3Eh
Tstates : 23.

ASM: SRL (IY+D)
OBJ: FDh, CBh, XX, 3Eh
Tstates : 23.

XX is the offset value.

Detailed info SUB

Operation: A = A - s
The s operand is subtracted from the contents of the accumulator, and the result is stored in the Accumulator.

ASM: SUB B
OBJ: 90h
Tstates : 4.

ASM: SUB C
OBJ: 91h
Tstates : 4.

ASM: SUB D
OBJ: 92h
Tstates : 4.

ASM: SUB E
OBJ: 93h
Tstates : 4.

ASM: SUB H
OBJ: 94h
Tstates : 4.

ASM: SUB L
OBJ: 95h
Tstates : 4.

ASM: SUB A
OBJ: 97h
Tstates : 4.

ASM: SUB n
OBJ: D6h, n
Tstates : 7.

ASM: SUB (HL)
OBJ: 96h
Tstates : 7.

ASM: SUB (IX+d)
OBJ: DDh, 96h, d
Tstates : 19.

ASM: SUB (IY+d)
OBJ: FDh, 96h, d
Tstates : 19.

Flags:

S: Set if result is negative, reset otherwise.

Z: Set if result is Zero, reset otherwise.

H: Set if borrow from Bit4, reset otherwise.

P/V: Set if overflow, reset otherwise.

N: Reset.

C: Set if borrow, reset otherwise.

Example: If Accumulator contains 29h, and register D contains 11h, after the execution of:

ASM: SUB D
OBJ: 92h

The Accumulator will contain 18h.

Detailed info XOR

Operation: A = A xor s
A logical exclusive-OR opperation is performed between the byte specified by the s opperand and the byte contained in the Accumulator, the result is stored in the Accumulator.

ASM: XOR B
OBJ: A8h
Tstates : 4.

ASM: XOR C
OBJ: A9h
Tstates : 4.

ASM: XOR D
OBJ: AAh
Tstates : 4.

ASM: XOR E
OBJ: ABh
Tstates : 4.

ASM: XOR H
OBJ: ACh
Tstates : 4.

ASM: XOR L
OBJ: ADh
Tstates : 4.

ASM: XOR A
OBJ: AFh
Tstates : 4.

ASM: XOR n
OBJ: EEh, n
Tstates : 7.

ASM: XOR (HL)
OBJ: AEh
Tstates : 7.

ASM: XOR (IX+d)
OBJ: DDh, AEh, d
Tstates : 19.

ASM: XOR (IY+d)
OBJ: FDh, AEh, d
Tstates : 19.

Flags:

S: Set if result is negative, reset otherwise.

Z: Set if result is Zero, reset otherwise.

H: Reset.

P/V: Set if parity even, reset otherwise.

N: Reset.

C: Reset.

Example: If the Accumulator contains 96h (10010110), and register D contains 5Dh (01011101) , after the execution of:

ASM: XOR D
OBJ: AAh

The Accumulator will contain CBh (11001011).