Talk:SDS 930

Latest comment: 5 years ago by Robin48gx in topic Old comments

Old comments edit

I have some old photos in the loft of one of these, and the front panel I will get them down and scan them sometime.

I think this computer is important being the first to move away from valves/tubes. In the documentation with it there was a statistical justification for moving to solid state (reliability stats of transistors vs. tubes).

Robin48gx 14:38, 28 December 2006 (UTC)Reply

First? Not by a long shot - see list of transistorized computers - 1964 was just about the *end* of the age of discrete transistors in mainframes.There were British,French, Polish and Chinese mainframes made of transistors, by then. The reference source I added says it was the first to use all silicon semiconductors, which might be true and a first. --Wtshymanski (talk) 00:47, 24 September 2009 (UTC)Reply

They were not fully tranistorised. AND we only got stuff like op-amps on a chip in the very late 60's. What do you think ? You could buy RAM chips in the 1960's ????

 Well I am not claiming that! It was in a sale brochure from the time.
 The logic DID appear to all be transistorised though. and sale brochures claimed it was the first fully transistorised computer. But it did 
 have CORE memory (i.e. magnetic core bits and the RAM was in a temperature controlled cabinet). I was commenting on the sale brochures that were bundled with it in the documentation. A marketing claim from the time!Robin48gx (talk) 15:47, 27 September 2018 (UTC)Reply

I worked on this computer and it was 23 bit + a sign bit. So it was not 2's complement (like all modern processors) it was something called sign magnitude.


To clarify, credentials of an editor are not as important on Wikipedia as citing sources. And you cannot guess a person's credentials or field of expertise from their user name. Several manuals are already scanned in at bitsavers, and both the 1966 and 1969 edition (using the XDS moniker) say it was two's complement. Page A-10. W Nowicki (talk) 00:16, 22 April 2011 (UTC)Reply
 Yes OK But I have notes for programming a calculator language (HP28S) I had at the time where I had to use
 sign and magnitude. So perhaps they changed to 2's complement at some~point after the one I used Robin48gx ([[User 
 talk:Robin48gx|talk]]) 15:47, 27 September 2018 (UTC)Reply