The Zilog Z8 is a

microcontroller A microcontroller (MC, uC, or μC) or microcontroller unit (MCU) is a small computer on a single integrated circuit. A microcontroller contains one or more CPUs (processor cores) along with memory and programmable input/output peripherals. Pro ...

architecture, originally introduced by

Zilog Zilog, Inc. is an American manufacturer of microprocessors, microcontrollers, and application-specific embedded System on a chip, system-on-chip (SoC) products. The company was founded in 1974 by Federico Faggin and Ralph Ungermann, who were soo ...

in 1979. Today the line also includes the Z8 Encore!, eZ8 Encore!, eZ8 Encore! XP, and eZ8 Encore! MC families. Signifying features of the architecture are up to 4,096 fast on-chip registers which may be used as accumulators, pointers, or as ordinary

random-access memory Random-access memory (RAM; ) is a form of Computer memory, electronic computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A random-access memory device allows ...

(RAM). A

16-bit 16-bit microcomputers are microcomputers that use 16-bit microprocessors. A 16-bit register can store 216 different values. The range of integer values that can be stored in 16 bits depends on the integer representation used. With the two ...

address space for between 1

kibibyte The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable un ...

(KB) and 64 KB of either

programmable read-only memory A programmable read-only memory (PROM) is a form of digital memory where the contents can be changed once after manufacture of the device. The data is then permanent and cannot be changed. It is one type of read-only memory (ROM). PROMs are used i ...

(PROM, OTP),

read-only memory Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing sof ...

(ROM), or

flash memory Flash memory is an Integrated circuit, electronic Non-volatile memory, non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for t ...

, are used to store code and constants, and there is a second 16-bit address space which can be used for large applications. On chip

peripheral A peripheral device, or simply peripheral, is an auxiliary hardware device that a computer uses to transfer information externally. A peripheral is a hardware component that is accessible to and controlled by a computer but is not a core compo ...

s include

analog-to-digital converter In electronics, an analog-to-digital converter (ADC, A/D, or A-to-D) is a system that converts an analog signal, such as a sound picked up by a microphone or light entering a digital camera, into a Digital signal (signal processing), digi ...

(A/D), Serial Peripheral Interface (SPI) and Inter-Integrated Circuit ( I²C) channels, IrDA encoders/decoders etc. There are versions with from 8 up to 80 pins, housed in dual in-line package (PDIP), Quad Flat No-leads package (MicroLeadFrame, MLF), small outline integrated circuit (SOIC), Shrink Small-Outline Package (SSOP), and low profile Quad Flat Package (LQFP). The eZ8 Encore! series can be programmed and debugged through a single pin serial communication interface. The basic architecture, a modified (non-strict)

Harvard architecture The Harvard architecture is a computer architecture with separate computer storage, storage and signal pathways for Machine code, instructions and data. It is often contrasted with the von Neumann architecture, where program instructions and d ...

, is ''technically'' very different from the

Zilog Z80 The Zilog Z80 is an 8-bit computing, 8-bit microprocessor designed by Zilog that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be Backward compatibility, software-compatible with the ...

. Despite this, the

instruction set In computer science, an instruction set architecture (ISA) is an abstract model that generally defines how software controls the CPU in a computer or a family of computers. A device or program that executes instructions described by that ISA, s ...

and

assembly language In computing, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence bet ...

syntax In linguistics, syntax ( ) is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure (constituenc ...

are quite similar to other Zilog processors: Load/store operations use the same LD mnemonic (no MOV or MOVEs), typifying instructions such as DJNZ, are the same, and so on. An

integrated development environment An integrated development environment (IDE) is a Application software, software application that provides comprehensive facilities for software development. An IDE normally consists of at least a source-code editor, build automation tools, an ...

(IDE) named Zilog Developer's Studio (ZDS) can be downloaded from Zilog's website including an assembler. The edition of ZDS II targeting Z8 Encore! and newer derivatives also includes a free compiler claiming ANSI C89 compliance. Primary competitors include the somewhat similar Microchip Technology PIC family, and all Intel 8051 descendants. Also more traditional ''

von Neumann architecture The von Neumann architecture—also known as the von Neumann model or Princeton architecture—is a computer architecture based on the '' First Draft of a Report on the EDVAC'', written by John von Neumann in 1945, describing designs discus ...

based'' single chip

s may be regarded as competitors, such as the Motorola 6800, 6809 based Motorola 68HC11, the Hitachi H8 family, and Z80-derivatives, such as

Toshiba is a Japanese multinational electronics company headquartered in Minato, Tokyo. Its diversified products and services include power, industrial and social infrastructure systems, elevators and escalators, electronic components, semiconductors ...

TLCS-870, to name only a few.

Product line

*ROMless: Models without integrated ROM *ROM: Models with integrated ROM *BASIC: Models with integrated BASIC interpreter and debugger in ROM *OTP: Models with integrated

(OTP ROM) *Low Voltage: Working voltage run as low as 2V *GP: General purpose microcontroller *Encore!: Integrated flash-based memory *Encore! XP: Encore! with sensors *Encore! MC (Motor Control): Motor control applications

Emulators

JTCEMU is a free software (

GNU General Public License The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first ...

(GPL) version 3) Z8 emulator written in

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

for

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

, and

macOS macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

Second sources

second sources" mode="packed"> Robotron UC8810D 004 1.jpg, VEB Kombinat Mikroelektronik Erfurt ''Karl Marx'' (MME) UC8810D (mask ROM version) Synertek Z8 03RS 1.jpg,

Synertek Synertek, Inc. was an American semiconductor manufacturer founded in 1973. The initial staff consisted of Bob Schreiner (the CEO), Dan Floyd, Jack Balletto, and Gunnar Wetlesen and Zvi Grinfas. Schreiner, Floyd, Balletto and Wetlesen were all forme ...

Z8-03RS (piggy-back EPROM version)

Notes

References

* Grehan, Rick (September 1994). "Processors Proliferate". ''

Byte The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable un ...

''.

External links

* {{Microcontrollers Microcontrollers Zilog microprocessors