Date   : Thu, 03 Apr 2008 15:51:25 +0100
From   : joel@... (Joel Rowbottom)
Subject: Wakefield Acorn Group 25th Anniversary

--On 3 April 2008 15:32:21 +0100 Andy Ford <acorn@...> wrote:

> Nice pics :)

Ta :)

> Although I am intrigued to know what those two "home made" computers
> (from the 60`s and 70`s) are about too :)

Mike Cook brought them along - the 60s one was his high-school CSE project, 
a binary adder. Twiddle the white knobs and the black knobs (two settings, 
1 and 0) and it would display the result on the lamps. If you added up 32 
and 64 it lit up the 32 and 64 lights, so you had to be a little more 
imaginative about what numbers you added up when doing a demo.

The 1973 one was a circuit he built to teach himself about how 
microprocessors worked. It had 256 bytes of memory, and programs could be 
stepped through since it used a static microprocessor (sorry, can't 
remember which one). He quipped that if nothing else, it taught him that 
wasn't how you built a computer :)