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On Friday 29 June 2012 21:46:20 Grant Edwards wrote: |
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> Things have been going steadily downhill since the days of V7 on a |
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> PDP-11 with 256K words of RAM, a 20MB hard drive and uucp via dial-up |
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> modems for "networking". Real programmers didn't _need_ more that |
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> 64k of text and 64k data to get the job done. |
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Sorry, but that's just bloat. When I joined the software development |
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effort on the national grid control system in 1980 (I was the third of |
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three) we had two Ferranti Argus 500 computers, one on-line and one |
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standby, each with 32KB RAM (twice as much as the same machines had at |
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the newly commissioning AGR power stations); 24-bit word length with |
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hardware key switches on the control panel (holy of holies). The three |
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disks were 2MB monsters, three feet six tall, five feet long and eighteen |
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inches wide, with air filtering systems we were supposed to know about |
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but Never Touch. Each disk could be connected to either CPU under |
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software control. The displays were graphic stroke writers, as used in |
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submarines and other warships - none of that nasty raster technology. I |
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think the display drivers were more complex than the CPUs - all that D-A |
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conversion of multiple values at once. Can you imagine X and Y amplifiers |
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to drive a spot in a circle - and meet up? Then a display full of them. |
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Those devices occupied as much cubicle space as the CPUs. Oh, and there |
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was a third machine (you wouldn't call it a box) for software |
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development. Paper tape for program I/O - not punched cards I'm glad to |
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say. |
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My boss was often called on to escort parties of power utility visitors, |
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mostly American, around the control centre. Their most common question |
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was "yes, I see the display drivers, but now where is your mainframe?" |
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Of course we didn't have one nor need one; we used subtle engineering in |
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those days rather than throwing money at the problem. That changed |
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later, but that's another story, and so is the use of PDP-11s in a minor |
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role. |
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Then the time came to replace that ageing technology. The man in charge |
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of the project complained to me once that, although he admired what we |
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were achieving, he couldn't freeze a user spec while we kept on making |
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the machine jump through ever-higher hoops. A proud moment for me - |
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there was still life in the old dogs yet, so why must they be replaced? |
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Not now, but I'll tell you some day about my proudest achievement in |
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assembler programming. Perhaps also what happened at three a.m. after |
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most bank holiday Mondays. Cyril might not like me telling you though. |
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As I said in the subject: OT. |
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-- |
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Rgds |
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Peter |