Centre for Computer History

 Intro

I visited the Centre For Computer History (CCH) in Cambridge for the second time in May 26.   It struck me that, for the most part, their history begins in the late 1970s.  To others it is a history of the first days of personal computers for business / entertainment / education.  For me it is a narrative of developments around the time I started using computers. 

Elliot 903

In December 1975, whilst in the sixth form at school, I was lucky enough to go on a week-long computer programming course hosted at Eton College.  They had their own computer, an Elliot 903 like the one shown in the picture, and a computer teacher, who ran our course.  This was the first computer I actually touched / operated.

I believe we learned programming in the Algol language, but I have no recollection of the details.  Once you had written a program (literally on a piece of paper), you typed it in on a teletype terminal, like the one shown, which put saved the program onto a paper tape.

The computer had no storage so you had to load the compiler on the computer by reading in a special (metal) tape, then you loaded your program paper tape so that the compiler could turn it into machine code.  At this stage the program was loaded in the computer memory and you could execute it.  I think you did this by setting switches on the computer panel.  The program would then run and could print any output on the attached teletype machine.  It was amazing.

Acorn System 1

In 1979 or 1980 we used the Acorn System 1, which is featured at CCH, in our practical classes at the computer laboratory in Cambridge.  This is a real piece of history as it was designed by Sophie Wilson (BBC micro designer, ARM founder) who had studied at the computer laboratory after switching from Mathematics in 1978.  She is three months older than me.  I was a year behind her and switched from Mathematics to the two-year computer science tripos in 1978.

Although the Acorn System 1 was based on what has become my favorite processor, the 6502, I struggled terribly with it as I was incapable of reading the "manual" which was printed in Upper Case in small letters with the lines close together.

Sinclair Spectrum

The Sinclair Spectrum (an early prototype board is shown) was announced in 1982 and I was aiming to make a fortune by writing software for it.  The idea was to create a software package to display 3D wire-frame objects which could be manipulated by moving or rotating them on the screen.  I drafted the programs, but unfortunately the computer didn't arrive for nearly a year by which time I had lost interest.  It did have the capability to save / load BASIC programs to cassette but it was somewhat clunky.  I recall that the game we used most was "The Hobbit" a text adventure game with pictures.  The aim was to to get Bilbo and friends through various tricky situations.

Apple I

This is a copy of the original Apple I computer designed, built and programmed by Steve Wozniak who, together with Steve Jobs, founded Apple. There weren't many originals sold, and a real one now sells for maybe $1million.  The primitive Operating System or "Monitor" enabled you to control the system. You could look at or update memory locations, enter programs (in machine code) and execute them.  Amazingly the monitor program, famously called WOZMON is only 250 bytes long.

The Apple 1 CPU is a 6502, which is the same one I use in my Ben Eater processor, BEN2.  It is wonderful that I am able to use that same code, written  in 1976 on my processor, to do the same tasks.

Apple II

The Apple II first went on sale in 1977 and had a great impact on the business computer world.  Until then specialist word processors (Wang) and some strange finance machines (Burroughts Visual Records Computer) were used in admin departments.
Apple II was designed by Steve Wozniak as a general purpose expandable personal computer.  Visicalc was the first "killer" PC app which invented the idea of spreadsheets.  It was simple but loved by Finance people.
I didn't actually use one until 1983 when I went to check out one at a shop in Kensingon where Theo Fennell (now) a famouse jeweller wanted to inventorise his stock.  He had hundreds of little packets containing diamonds.  I'm afraid I recommended an IBM PC as more practical for his database catalog.

BBC Micro

 

The BBC micro or "beeb" was built by Acorn for a major computer literacy education initiative by the BBC in 1981.  Steve Furber mainly designed the hardware and Sophie Wilson wrote BBC Basic.  It was widely used and provided many peoples introduction to computers.

Annette purchased a machine for Alex in about 1995.  It came with a monitor, a touch screen attachment and some educational games.  The touch screen was a wild idea 30 years ago.  It had a grid of infra-red sensors surrounding the screen surface.
Touching the screen with a finger interrupted a vertical and horizontal sensor, giving you a screen position.  I recall writing a BASIC program for an on screen calculator which Alex could use without a keyboard.