ZiLOG Z80 Handbook

CHAPTER 5
Instruction Set
The table of addressing modes given in Chapter 4 cross-references
Z-80 instructions with its addressing modes. For discussion pur-
poses, the instruction repertoire of the Z-80 may be classified into
the groups shown in Chart 4-1. These groups are:
1. 8-Bit Load
2. 16-Bit Load
3. Exchange, Block Transfer, and Search
4. 8-Bit Arithmetic and Logical
5. General-Purpose Arithmetic and CPU Control
6. 16-Bit Arithmetic
7. Rotate and Shift
8. Bit Set, Reset, and Test
9. Jump
10. Call and Return
11. Input and Output
8-BIT LOAD GROUP
The 8-Bit Load Group is shown in Table 5-1. About half of the
instructions in this group load an 8-bit value into a CPU register
from another CPU register, immediate value in the instruction, or
memory location. The other half of the instructions store an 8-bit
value from a CPU register or immediate value into a CPU register
or memory location. In all cases, the source register remains un-
changed after the transfer.
Four of the instructions simply transfer the contents of the I and
R registers into the current A register and vice versa. LD A,I loads
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ZiLOG Z80 Specifications

General

Manufacturer	ZiLOG
Introduction Year	1976
Clock Speed	2.5 MHz to 20 MHz
Data Width	8-bit
Address Width	16-bit
Instruction Set	Z80
Transistor Count	8, 500
Package	40-pin DIP
Category	Microprocessor
Memory Address Space	64 KB
Voltage Supply	5V