View source for PSI Comp 80

The '''PSI Comp 80''' was a [[home computer]] sold by Powertran starting in 1979. It was sold in the form of a [[Electronic kits|kit]] of parts for a cased [[Single-board computer|single-board]] home computer system.
The system was based on a [[Zilog Z80|Z80]] [[microprocessor]] addressing a mixture of 8 [[kilobyte|KB]] of system [[RAM]] and [[EPROM]], plus 2 KB of [[video RAM]].
It used a [[National Semiconductor]] MM57109N as a [[math co-processor|mathematical co-processor]] to speed up calculations.
==History and specifications==
In 1979, the British magazine ''[[Wireless World]]'' published the technical details for a "Scientific Computer".<ref>{{Cite book|url = https://archive.org/details/PSIComp80-WirelessWorld-1979-80|title = PSI Comp 80 from Wireless World 1979-80|last = J H Adams|date = 1979-01-01}}</ref> Shortly afterward the British firm Powertran used this design for their implementation, which they called the PSI Comp 80.
Ahead of its time, it incorporated a [[Coprocessor|number crunching coprocessor]] and a novel language embedded in EPROM called Basic Using Reverse Polish - BURP.
The monochrome [[Video display controller|Video Display Controller]] could simultaneously display combinations of 32 lines of 64 characters, and 128 x 64 resolution graphics by either displaying a normal character or a "[[semigraphics|pseudo graphics]]" character, with [[pixel]] blocks in a 2x2 matrix. A technique similar to the one used in the [[TRS-80]] - It could later be expanded to a higher resolution, although never to colour.
Add-ons were developed for the system, including memory expansions, floppy and hard disk interfaces, various software packages and a disk [[operating system]], SCIDOS, which was [[CP/M]]-compatible but also included features - [[Directory (computing)|structured (pathed) disk folders]], etc. - now very familiar to modern-day PC users.
During the mid-1980s, the designer of this system, John Adams [[Master of Science|M.SC.]], published a new version of the Scientific Computer - the SC84 (Scientific Computer of 1984). It was based upon a [[backplane]] and plug-in cards and modules and featuring a [[Hitachi]] [[HD64180]] processor, up to 512 kbytes of [[random-access memory|RAM]] and a high-resolution colour graphics system.
==References==
{{reflist}}PSI 2020
==External links==
* [http://www.zonadepruebas.com/modules/smartsection/item.php?itemid=788 a picture of the advertisement for the PSI Comp 80 in Wireless World]
* [https://vintagecomputers.sdfeu.org/comp80/ Links to Wireless World articles]
* [http://www.computinghistory.org.uk/det/22148/SC84/ SC84 article]
[[Category:Home computers]]
[[Category:Computer-related introductions in 1979]]
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