Ira Goldklang's TRS-80 Revived Site

Z-80 Machine Language Quick Guide

        



         Z80 Machine Language Quick Guide (c) Mary Bell
Mary created this guide to the Z80 machine code and Assembly instruction set mostly for my own purposes while using a Z80 and the Radio Shack TRS-80's, so thought it might be of use to others when learning or editing code. The guide consists of a series of tables not unlike the original Zilog Z80 Reference Manual, with signifigant changes to make the act of coding or decoding a program less clumbersome. The HTML versions are a little bit cluttered, so I recommend the graphical representations at the end of the page to be printed or followed for the construction of a 3x5 table for use by hand. Use of the tables themselves is un-restricted for non-commercial purposes.


         Jumps & INCs 00 to 3F

1's

16's>

0

1

2

3

0

JR

NOP

DJNZ

NZ

 NC

1

nn->

BC

DE

HL

SP

2

A->

(BC)

(DE)

(HL)

(nn)

3

INC

BC

DE

HL

SP

4

INC

B

D

H

(HL)

5

DEC

B

D

H

(HL)

6

n->

B

D

H

(HL)

7

 

RLCA

RLA

DAA

SCF

8

JR

AF<->AF'

UNC

Z

C

9

HL+

BC

DE

HL

SP

A

->A

(BC)

(DE)

(nn)->(HL)

(nn)

B

DEC

BC

DE

HL

SP

C

INC

C

E

L

A

D

DEC

C

E

L

A

E

n->

C

E

L

A

F

 

RRCA

RRA

CPL

CCF

1's

16's>

0

1

2

3

         Call & Pushes C0 to FF

1's

16's>

C

D

E

F

0

RTN

NZ

NC

PO

NM

1

POP

BC

DE

HL

AF

2

JMP (nn)

NZ

NC

PO

NM

3

 

JMP (nn)

OUT (n)

HL<->(SP)

DIS INT

4

CALL (nn)

NZ

NC

PO

NM

5

PUSH

BC

DE

HL

AF

6

A/n

+

-

AND

OR

7

RST

00h

10h

20h

30h

8

RTN

Z

C

PE

M

9

 

RTN

EXX

JMP (HL)

HL->SP

A

JMP (nn)

Z

C

PE

M

B

 

CNTL BITS

IN (n)

HL<->DE

ENA INT

C

CALL (nn)

Z

C

PE

M

D

 

CALL (nn)

IX for HL

Ext Ins

IY for HL

E

A/n

+/cy

-/cy

XOR

CP

F

RST

08h

18h

28h

38h

1's

16's>

C

D

E

F

         Extended Instructions ED+n

1's

16's>

4

5

6

7

A

B

0

IN(c)

B

D

H

 

LDI

LDIR

1

OUT(c)

B

D

H

 

CPI

CPIR

2

HL-/cy

BC

DE

HL

SP

INI

INIR

3

->(nn)

BC

DE

 

SP

OUTI

OUTIR

4

 

NEG

 

 

 

 

 

5

 

RET NMI

 

 

 

 

 

6

 

IM0

IM2

 

 

 

 

7

 

A->I

I->A

RRD

 

 

 

8

IN(c)

C

E

L

A

LDD

LDDR

9

OUT(c)

C

E

L

A

CPD

CPDR

A

HL+/cy

BC

DE

HL

SP

IND

INDR

B

(nn)->

BC

DE

HL

SP

OUTD

OUTDR

C

 

 

 

 

 

 

 

D

 

RET MI

 

 

 

 

 

E

 

 

IM2

 

 

 

 

F

 

A->R

R->A

RLD

 

 

 

1's

16's>

4

5

6

7

A

B

         Register Ops 40 to 7F

source reg

operations w/A

B

C

D

E

H

L

(HL)

A

+/cy

-/cy

XOR

CP

C

E

L

A

8

9

A

B

C

D

E

F

<1's

+

-

AND

OR

B

D

H

(HL)

0

1

2

3

4

5

6

7

<1's

16's>

8

9

A

B

4

5

6

7

Ex: 9A=SBC A,D

move destination

Note: 76=HALT

         Control Bits CB+ 00-FF

Source Reg

Ex: CB 5A=TEST BIT 3,D

B

C

D

E

H

L

(HL)

A

BIT#

1's>

8

9

A

B

C

D

E

F

1

3

5

7

RRC

RR

SRA

SRL

<ops

1's>

0

1

2

3

4

5

6

7

0

2

4

6

RLC

RL

SLA

 

<ops

16's>

SET>

C

D

E

F

0

1

2

3

<16's

16's>

RESET>

8

9

A

B

<16's

16's>

TEST>

4

5

6

7

<16's

         Graphics Version

In case you want to print this out full page and then cut it apart and paste to 3 by 5 cards for a home-made handy reference.