CZ80CPU

8-bit Microprocessor Core

CAST, Inc.

April 2003

Page 1

General Description

Implements a fast, fully-functional, single-chip, 8-

bit microprocessor with the same instruction set

as the Z80.

The core has a 16-bit address bus capable of

directly accessing 64kB of memory space. It has

252 root instructions with the reserved 4 bytes as

prefixes, and accesses an additional 308

instructions. The microcode-free design is strictly

synchronous, with no internal tri-states and a

synchronous reset.

Developed for easy reuse in Actel FPGA

applications, the CZ80CPU is available optimized

for several device families with competitive

utilization and performance characteristics.

Symbol

Features

Programming features contain 208 bits of

read/write memory that are accessible to the

programmer. The internal registers include an

accumulator and six 8-bit registers that can be

paired as three 16-bit registers. In addition to

general registers, a 16-bit stack-pointer, 16-bit

program-counter, and two 16-bit index registers

are provided.

o 8-bit Instruction decoder

o 8-bit arithmetic and logical operations

o 16-bit arithmetic operations

o Boolean manipulations

o Duplicate set of both general purpose and

flag registers

o Two 16-bit index registers

o Three modes of maskable interrupts

o Non maskable interrupt

o Can address up to 64 KB of program

memory

o Can address up to 64 KB of data memory

o Can address up to 64 KB of input/output

devices

Applications

Suitable for many embedded controller

applications, including industrial control systems,

point-of-sale terminals, and automotive controls.