Date   : Sun, 03 Jan 1999 14:18:33 +0100
From   : "Mark Usher" <marku@...>
Subject: Re: Using PC keyboards & PC cases

> Oh Mark, IhateyouIhateyouIhateyou.  I've got a spare PC tower case doing
> nothing here and only last week boxed up my Beeb and all the bits and
> put it in the loft.  Now you've planted the idea in my head, I'm not
> going to be able to resist doing a conversion!  Tsk.  I've just given
> away my monitor as well.
What a sod I am. I'd been toying with the idea for ages. I had build 3
floppies and a hard drive into a desktop case with ribbon cables trailing
out the back and up into the beeb, but this was all taking desktop space.

> The more I think about it, the more obvious it seems.  The floppy drives
> will fit perfectly, the PC speaker can be used, the PC PSU is amply
> specced and has cooling, there's plenty of room for z80 and shadow RAM
> boards, a hard disc will be easy to fit and the adapter boards can be
> mounted in spare 5.25" bays, the LED speed readout on the front of the
> case can be altered to read 2(MHz) or perhaps even 'BBC'.
Exactly. I have a 6502 co-pro and so it was wired to read 2 or 3 MHz :-)
There is also plenty of room for an extra fan to blow across the
motherboard.
I was luck in that the part of the case where the mainboard attaches
unscrews and comes completely away. So I was able to secure the BBC board
very well and easily working on a my desk instead of on the floor.

> The hole for the keyboard socket on the case would be perfect for a
> monitor plug.
Bingo.

> >- the reset switch also neatly attached
> wire it in parallel with the Break key...
Yes it is, directly to the two solder holes on the back of the mainboard.
Why aren't they closer together for jumper pins.

> >(although a reset never works correctly when I
> >turn on the co-pro and then reset - it always boots to the *
> prompt instead
> >of >).
> hold down Ctrl when pressing reset...
Silly me. Yes it's OK. Shame though that you still have to press a key on
the keyboard at the same time - sort of defeats the object of a switch on
the case. Any way to hardwire this to CTRL too ?

> >All I have to do is respray the case
> black?  Beeb beige?  blue with pink spots?
I was thinking of Beeb beige with some red. Also the Owl on that large space
at the bottom . I want to fit a couple of switches though aswell to switch
the Hard drive and floopy drive ID's so that I can use the two 5.25's and
3.5 in any configuration.

> > and somehow make a decent keyboard extension.
> find a curly cable with at least 17 ways and two 34 way IDC connectors
> salvaged from a scrap floppy cable.  A bit of careful fiddling with a
> vice, and presto!  Or advertise for a Viglen kit, throw away the desktop
> bit and keep the keyboard housing and cable.
This could be the thing. Ribbon cable is easy but it looks a little messy.
The Viglen kit would be nice for the keyboard housing, but I could always
make a small one with some plywood. I am loathe to cut the BBC's case. I
just couldn't do it.

> Alternatively, you can buy flexible braided tubing (anyone who has seen
> the SCSI cable used in IBM PS/2 machines will know what I mean).  You
> could split a 34 way ribbon cable about every 5 strands (to make it
> flexible), leaving the ends intact to allow clamping into IDC
> connectors,  and then work it into this tubing - should look quite neat.
Ahh - now this is quite elegant. I'll just have a look on the RS CD to see
what they've got, or I could make some sort of infa red transmitter from one
of the kits........


Mark