Scor­pio News


July–September 1987 – Volume 1. Issue 3.

Page 9 of 67

Pluto upgrade saga

Every 80-BUS user who isn’t immensely wealthy must have had the Pluto 2 on his wish list for ages now. If I had won on the pools, I would have three Pluto 2’s linked together to provide proper colour graphics, with each pixel being any one of a range of over 16 million colours. Regrettably, though, the foolish football teams persistently get their scores wrong, and that remains a wish. All I can hope to do is upgrade the Pluto 1 as far as I can manage.

The first thing I considered was something called “the double speed processor kit” in old price lists, which used to sell for £60, and was supposed to give a 60% increase in the work rate. I assume the other 40% was eaten by memory wait states, or some such phenomenon. This kit seems not to be available any more, and the people at Io Research didn’t seem to have heard of it. Still, I had a way to make things go a little faster, by replacing the 8088 processor with an NEC V20, which thankfully has now come down to a sensible price.

I needed a benchmark of some sort, so I rewrote my Union Jack program so it repeated itself ten times, to make timing easier. With the 8088, it took 26 seconds; with the V20, this was reduced to 19 seconds. All very satisfactory, as far as it went, but I still could only produce eight colours. You can actually produce very good effects that look like more colours, just by putting together two different coloured pixels side by side, since they are so small, but it’s not the same as having 16 million colours to play with, or even 4096.

In the hope of making savings by assembling something myself, I wrote to Io Research and tried to buy a bare board and parts list for either the paletteboard or the mini palette board. Io Research are a very unusual firm! Not only do they answer my letters, but when they say they will phone back, they always do. I don’t want to go too far over the top and embarrass them, but their standard of service makes a very refreshing change these days. Cynics may think I wrote that because Io managed to find a spare mini palette board for me, in spite of the fact they stopped making them over two years ago, but cynics are wrong on this occasion. I have not yet finished the installation of the improved board, so I am unable to go into raptures about the 4096 colours, as yet, and still am not sure I have made the right links inside my Microvitec monitor. I think I am going to have to put some sort of switch gear in the monitor, as it will soon be used by more than one machine. You will read about it all here, when I get it going.

Local firm in interview shock horror probe!

Amazingly, a quite large computer communications firm actually interviewed me in March. The interviewer seemed interested in the Open University courses I had been studying, and it all seemed to go quite well. They are now two months overdue on their promise to “let me know”, and ignored the telex message I sent them about this. I can only assume they are trying to avoid Dr Dark’s curse, which results in every firm that turns me down going broke, without having to take me on. The curse is real, folks: Quest Automation and DJAI Systems found out the hard way! (Although somebody later baled Quest out by buying them up.) Si, I still have my dull job. Maybe I could be a lumber jack?

Information wanted

The loan of any documentation for the following items would be very welcome indeed: the Gemini real time clock board, the Iotec Iona (heavy), and a huge S100 system with two 8″ drives and the words “Sytem III” on the front (very heavy.) I will gladly pay postage both ways for suitable manuals to look at.

Old thingies for sale dead cheep

For the poverty stricken enthusiast, I have a Nascom 1 in poor health. This would make an interesting restoration project for a masochistic enthusiast. The Nascom 1 has about half its chips missing, although all the RAM is there. The keyboard seems to be unbroken. There is a 3 amp Nascom PSU, with no transformer, and some other parts missing. I have a Nascom 1 construction guide

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