--- title: Feedback ABACUS Educational Computer categories: - Computers types: - Professional Computer origins: - United Kingdom years: - '1971' cpus: - Circuit module params: name: ABACUS Educational Computer company: /companies/feedback company_name: Feedback specs: - label: NAME value: ABACUS Educational Computer - label: MANUFACTURER value: Feedback - label: TYPE value: Professional Computer - label: ORIGIN value: United Kingdom - label: YEAR value: '1971' - label: BUILT IN LANGUAGE value: None - label: KEYBOARD value: 36 Input keys and 4 Function keys - label: CPU value: Circuit module - label: SPEED value: 250 Hz. (4 ms per instruction except Multiply & Divide - label: CO-PROCESSOR value: None - label: RAM value: 1 KB of ferrite core storage organised as 512 off 2-byte (16 bit) - label: ROM value: No ROM - label: TEXT MODES value: Hard copy and punched paper tape output via ASR33 Teletype - label: SOUND value: No sound - label: SIZE / WEIGHT value: 78.7 (H) x 50.8 (W) x 29.2 (D) cm. / 22.4 Kg - label: I/O PORTS value: Teletype connector - label: BUILT IN MEDIA value: Non volatile memory - label: POWER SUPPLY value: Built-in power supply unit - label: PRICE value: £1800. tabs: - photos photos: - title: SYSTEM subtitle: '' text: '' image: null - title: TOP VIEW subtitle: '' text: '' image: null - title: IN USE subtitle: '' text: '' image: null - title: DETACHABLE KEYBOARD subtitle: '' text: '' image: null - title: KEYBOARD CLOSE-UP subtitle: '' text: '' image: null - title: FRONT PANEL subtitle: '' text: '' image: null - title: FRONT PANEL IN USE subtitle: '' text: '' image: null - title: BACK SIDE OPENED subtitle: '' text: '' image: null - title: SYSTEM CARDS subtitle: '' text: '' image: null - title: 1024 BIT CORE MODULE subtitle: '' text: '' image: null - title: 'CORE MEMORY #1' subtitle: '' text: '' image: null - title: 'CORE MEMORY #2' subtitle: '' text: '' image: null - title: 'CORE MEMORY #3' subtitle: '' text: '' image: null - title: EC-362 FRONT PANEL subtitle: '' text: '' image: null - title: EC-362 KEYBOARD subtitle: '' text: '' image: null - title: FULL SYSTEM BACK subtitle: '' text: '' image: null - title: FULL SYSTEM - INSIDE subtitle: '' text: '' image: null - title: FULL SYSTEM - FRONT SIDE subtitle: '' text: '' image: null - title: FULL SYSTEM RUNNING subtitle: '' text: '' image: null - title: FULL SYSTEM - KEYBOARDS subtitle: '' text: '' image: null comments: - author: Paul (ISRAEL ) date: Saturday 10th September 2022 text: I learned logic and computer basics on an Abacus unit in ISRAEL in 1973. It used serial ALU and logic. It was AMAZING. - author: Johannes Schacht (Deutschland) date: Tuesday 29th December 2020 text: Would anyone have technical information on the computer? - author: William.winnt.net (Soule/southKorea) date: Sunday 10th June 2018 text: |- Company. BLUEFIN.NETWORK.COM (founder/author)\ MICROSOFT TRUE OWNERSHIP,WILLIAM.WINN.TAYLOR.COMPANY\ GOGGLE, YAHOO! , CHROME - author: Charles Razzell date: Wednesday 16th November 2011 text: |- My secondary school classroom (in Crowborough, E. Sussex) had an Arithmetic Unit from the ABACUS Educational Computer that was kindly donated to the school by Feedback. This was in 1971 and the school was Crowborough Beacon Comprehensive. I had a lot of fun playing with the machine, either single stepping though binary arithmetic or playing a game of "yellow lights vs. white lights," where the objective was to take turns doing a computation that would increase the number of your chosen color at the expense of the opponent''s color. I like to tell my children that I''m so old, my first computer was an ABACUS! - author: jon date: Sunday 19th September 2010 text: What is an abacus and how is it related to the computer? - author: Martin MacLeavy (Kingston Jamaica) date: Friday 6th February 2004 text: |- There was a version of the ABACUS at the C&W Engineering College, Porthcurno, Cornwall on which I cut my teeth in the programming field. I am interested in getting a circuit diagram for it if its available. Regards - author: Brian Townsend (Near Chelmsford, England, UK) date: Thursday 4th September 2003 text: |- I contributed this system to old-computers after rescuing it from possible destruction. I was actually responsible for its purchase for the college in which I worked and I taught computer programming principles to a large number of students using the system.\ If you were one of my students and want to recall those early days (in the 70's) when computing was in its infancy, then leave a message for me. oc_id: 821 source: url: https://web.archive.org/web/20230607054056/http://www.old-computers.com/museum/computer.asp?c=821 date: '2023-06-07' --- The computer system consisted of two units - **EC362** and **EC372** - that could be used independently or linked together to provide a complete system for computer education. To enable the input of relatively long programs and the output of computed results, an ASR33 Teletypewriter with 8-hole punched paper tape input and output was connected to the two linked units. In addition, a textual output was printed on an 8 inch (200 mm) wide paper roll. Unit EC362 was the Arithmetic Unit and unit EC372 was the Core Store and Control Unit. Both units had the same physical size (about 1m high x 600mm wide x 600 mm deep) and the large size allowed the units to be used in a classroom, either singly or jointly, in a demonstration mode. Each unit had a removable, push button, input console connected to its parent unit via a long connector. This feature allowed input and control of the units at the same time as allowing students a full view of the mimic diagrams on the front of the units. The lamps on the mimic diagrams could be arranged in groups of either three or four yellow and white lenses. This feature provided the opportunity to use OCTAL coding or HEXADECIMAL coding without having to make wiring changes. The use of different groupings of the coloured push button key tops provided the same facility for input coding. Behind each of the removable consoles was a set of switches that were used to insert predetermined fault conditions to allow the teaching of faultfinding procedures. Special thanks to **Brian Townsend** who gave us this venerable machine.