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Sinclair ZX80
Sinclair ZX80
Type Home computer
Released 1980
Discontinued 1981
Processor Z80 @ 3. A home computer was a class of Personal computer entering the market in 1977 and becoming common during the 1980s The Zilog Z80 is an 8-bit Microprocessor designed and sold by Zilog from July 1976 onwards 25 MHz (most machines used the NEC μPD780C-1 equivalent)
Memory 1 KB (16 KB max. is a Japanese multinational IT company headquartered in Minato Tokyo, Japan. )
Operating system Sinclair BASIC

The Sinclair ZX80 was a home computer brought to market in 1980 by Sinclair Research of Cambridge, England. A home computer was a class of Personal computer entering the market in 1977 and becoming common during the 1980s Year 1980 ( MCMLXXX) was a Leap year starting on Tuesday (link displays the 1980 Gregorian calendar) Sinclair Research Ltd is a consumer electronics company founded by Sir Clive Sinclair in Cambridge, England (originally as Sinclair Radionics in 1961 to It was notable for being the first computer available in the United Kingdom for under a hundred pounds (a price tag of £99. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located The Pound Sterling ( symbol £; ISO code: GBP) subdivided into 100 pence (singular penny) is the Currency 95, to be exact). It was available in kit form, where purchasers had to assemble and solder it together, and as a ready-built version at a slightly higher cost for those without the skill or inclination to build their own unit. The ZX80 was very popular straight away, and for some time there was a waiting list of several months for either version of the machine.

Contents

Description

The machine was designed by Jim Westwood around a Z80 central processing unit with a clock speed of 3. Jim Westwood was the chief Engineer at Sinclair Research Ltd in the 1980s starting at the company in 1963 The Zilog Z80 is an 8-bit Microprocessor designed and sold by Zilog from July 1976 onwards The clock rate is the fundamental rate in cycles per second (measured in Hertz) at which a Computer performs its most basic operations such as adding two 25 MHz[1], and was equipped with 1 KB of static RAM and 4 KB of read-only memory containing the Sinclair BASIC programming language, editor, and operating system. A kilobyte (derived from the SI prefix Kilo -, meaning 1000 is a unit of Information or Computer storage equal to either 1024 Static random access memory (SRAM is a type of Semiconductor memory where the word static indicates that unlike ''dynamic'' RAM (DRAM, it does not Sinclair BASIC (taking its name from innovator Sir Clive Sinclair) is a dialect of the BASIC Programming language used in the 8-bit Home A programming language is an Artificial language that can be used to write programs which control the behavior of a machine particularly a Computer. An operating system (commonly abbreviated OS and O/S) is the software component of a Computer system that is responsible for the management and coordination BASIC commands were not entered by typing them out but were instead selected somewhat similarly to on a scientific calculator - each key had a few different functions selected by both context and modes as well as with the shift key.

Display was over an RF connection to a household television, and simple offline program storage was possible using a cassette recorder. The video display generator of the ZX80 used minimal hardware plus a combination of software to generate a video signal. As a result of this approach the ZX80 could only generate a picture when it was idle, i. e. waiting for a key to be pressed. When running a BASIC program, or even when pressing as key for any input, the display would, therefore, black out momentarily to support the function. This made moving graphics difficult since the program had to introduce a pause for input to display the next change in graphical output. The later ZX81 improved on this somewhat because it could run in a 'slow' mode while creating a video signal, or in a 'fast' mode without generating a video signal (typically used for lengthy calculations). The Sinclair ZX81 Home computer, released by Sinclair Research in 1981, was the follow up to the company's ZX80.

A ZX81 8 KB ROM was available to upgrade the ZX80 and cost around 20% of a full blown ZX81. The Sinclair ZX81 Home computer, released by Sinclair Research in 1981, was the follow up to the company's ZX80. The Sinclair ZX81 Home computer, released by Sinclair Research in 1981, was the follow up to the company's ZX80. It came with a thin overlay keyboard and ZX81 manual. Simply taking off the top cover of the ZX80 and prying the old ROM from its socket and carefully inserting the new ROM and adding the keyboard overlay, the ZX80 would now function almost identically to the proper ZX81 except for SLOW mode, and this was purely down to hardware differences. The process was easily reversed to get the ZX80 back to its old self.

Sinclair also produced RAM expansion packs for the ZX80; the original ZX80 RAM Pack held either 1, 2 or 3 KB of static RAM, a later model held 16 KB, using dynamic RAM chips (DRAM). There was no upgrade for the monochrome display however.

The machine was mounted in a tiny white plastic case, with a one-piece blue membrane keyboard on the front; it owed its distinctive appearance to industrial designer Rick Dickinson. A membrane keyboard is a Computer keyboard whose "keys" are not separate moving parts as with the majority of other keyboards but rather are Pressure pads Rick Dickinson was the in-house Industrial designer of Sinclair Research Ltd. There were problems with durability, reliability and over-heating. The entire system was about the size of two paperback books placed beside each other. Crude it might have been, but the ZX80 was a true innovator and it kick-started the 1980s home computer craze in the UK and New Zealand. It was superseded by a number of other Sinclair machines, notably the Sinclair ZX81 and the very successful ZX Spectrum. The Sinclair ZX81 Home computer, released by Sinclair Research in 1981, was the follow up to the company's ZX80. The Sinclair ZX Spectrum is an 8-bit personal Home computer released in the United Kingdom in 1982 by Sinclair Research Ltd

Sales of the ZX80 reached about 50,000 — an unheard of number for the day which contributed significantly to the UK leading the world in home computer ownership through the 1980s. Owing to the unsophisticated design and the tendency for the units to overheat, surviving machines in good condition are quite uncommon and can fetch high prices by collectors.

Internal workings

The ZX80 was designed around readily available TTL chips; the only proprietary technology was the firmware. While the successor ZX81 used a semi-custom chip (an ULA or Uncommitted Logic Array), this merely combined the functions of the earlier hardware onto a single chip — the hardware and system programs (except the BASIC versions) were very similar, with the only significant difference being the NMI-generator necessary for slow mode in the ZX81. A gate array or uncommitted logic array ( ULA) is an approach to the design and manufacture of Application-specific integrated circuits (ASICs A non-maskable interrupt ( NMI) is a computer processor Interrupt that can not be ignored by standard interrupt masking techniques in the system (See ZX81 for technical details. The Sinclair ZX81 Home computer, released by Sinclair Research in 1981, was the follow up to the company's ZX80. ) Both computers can be made by hobbyists using commercially available discrete logic chips or FPGAs.

Different flavors

There were also Americanized versions of the ZX80/ZX81 (Micro Ace / Timex Sinclair 1000 or TS1000 respectively). The Sinclair ZX81 Home computer, released by Sinclair Research in 1981, was the follow up to the company's ZX80. The Timex Sinclair 1000 (TS1000 was the first A list can be found at Herr Liebert's ZX80/ZX81 User's Group web site (in Deutsch or English).

External links

footnotes

  1. ^ This frequency was critical, as the TV picture generation depended on it (see ZX81). The Sinclair ZX81 Home computer, released by Sinclair Research in 1981, was the follow up to the company's ZX80.
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