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 3×5 table for use by hand. Use of the tables themselves is un-restricted for non-commercial purposes.

Jumps & INCs 00 to 3F

Call & Pushes C0 to FF

Extended Instructions ED+n

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.