Scor­pio News

  

July–September 1988 – Volume 2. Issue 3.

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tried in the 132 by 43 mode, in colour, and results were quite acceptable as far as screen definition was concerned, although this is obviously more a function of the EGA card and Monitor, than the computer itself. There was not sufficient time to try to word-process with WS in this mode to see whether the program behaved correctly.

The system speed is most impressive. Hard disk performance is very good. Wordstar Overlays load from the hard disk almost before one has had time to look up from the keyboard, and programs load extremely quickly. I have not carried out any accurate quantitative tests on this, but Supercalc 3, for example loads almost instantly, compared with several seconds on an ‘XT’. On a Gemini Galaxy 2 system, Supercalc 2 took about 7 seconds to load to the first screen, from floppy, and about 2 seconds from Hard Disk.

After I had used the system for a short while, I found it tedious compacting software from 360K disks on to 1.2Mb disks by copying onto and then off of the Winnie, and I also wanted to write to and format 360k disks, so I decided to try to use a Teac FD55B that was available, as drive B:. I replaced the short cable running from the 34 way connector on the main PCB, to the 1.2Mb floppy, with another longer cable.

This new cable was fitted with two 34 way card edge (floppy type) connectors, one of these connectors being about 3 feet away from the first. The cable to this ‘remote’ connector was placed through one of the unused expansion slot covers, which was then replaced and lightly tightened, and the connector plugged in to the FD55B, (which had a separate PSU). I then re-ran SETUP to tell the system that drive B: existed as a 360k drive, and rebooted. After sorting out a couple of wires, all was OK. and I had a 360k drive online. The sorting out of the ‘couple of wires’ was a bit of a problem for a while.

IBM, in their wisdom, decided that line 10 should be motor 1 on/off, line 12 drive 1 select, line 14 drive 2 select, and line 16 motor 2 on/off. In order for this to work, some modification of the standard ‘Shugart’ arrangement was needed, and was solved by Gemini splitting the ribbon cable between lines 9 and 10, and 16 and 17, and then twisting lines 10-16 so that these seven lines are reversed where they enter the first floppy drive.

When the system asserts line 10 for motor or line 12 for select drive, these arrive on pins 16 and 14 of the first drive respectively; and provided that the correct drive select jumper is inserted in the drive, the drive works correctly. In extending the cable to another external drive, I then had to get line 10 (= line 16 before the twist = motor 2 on/off) back to line 16 so as to operate the motor in the second drive. This was accomplished by cutting lines 10 and 16 of the cable, and cross-connecting them as needed.

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