Date   : Sun, 21 Dec 1997 11:29:15 +0100
From   : "Mark Usher" <marku@...>
Subject: Re: Hard Drives

Hi Crispin

>I've just been looking at the old messages to the mailing list, the ones
>from about 1992 or thereabouts, and I have been reading a lot of messages
>about someone who produced an SCSI controller board for the BBC, so that
>any SCSI device could be connected, the total cost then was about £35, so
>it should have fallen a bit by now.
Not by so much, the price of £35 is mostly for all the bits and pieces, p&p,
connectors, cables etc etc. It can soon mount up.


>Anyway, I was wondering, is anyone still on here that knows how to make/has
>a controller board for the BBC, and if so what drives are compatible?

Look in the documentation section of the BBC lives, I uploaded this about 2
weeks ago.
As for compatability with SCSI, I don't know,  and I'm still trying. I'm not
sure if it is my adapter board or the software I'm using to try and format
it.

>I have a big PC power supply, which I ripped out of a broken computer, and
>then laughed heartily at how my 10 year old beeb could out last a 4 year
>old pc! This I use to connect 2 80t double sided drives, and could use to
>power a hard disk, so all I need is the board, a 1770 controller, an SCSI
>controller, ADFS, and some money - is this correct?

Not quite, you can run a hard disk with ADFS WITHOUT a 1770 controller, it's
just that you'll also need the standard 8271 DFS also in the BBC so that you
can use your floppy too. The 1770 allows you to use the floppys with ADFS so
that you will save yourself a ROM socket. Also the 1770 and it's DFS is
better than the 8271 and you will have less problems connecting the more
modern floppy drives.

>Also, I want to add two 3 1/2 inch drives to the beeb, will it work with
>1.44mb drives in 720k mode?  My ultimate aim is to have 2 3 1/2 inch
>drives, and then one 5 1/4 inch drive to run the old software which can't
>be copied.  Can I add three drives in to the beeb, which can be used at the
>same time?  Or do I have to add in a selector switch to add in the 5 1/4
>inch drive at the expense of one of the 3 1/2 inch drives, so I could
>either have 1 3 1/2 inch, and 1 5 1/4 inch drive, or two 3 1/2 inch drives.
> Can someone help me with this?

Yes, it is quite common for people to do this.
Look in the 8BS issues, one of them had an article that stated how to wire
this up.

>One last thing - does anyone have the information to build the Micro User
>real time clock? A scanned copy would do, the article is in the Feb 1984
>Micro user if anyone has got that.
There are archives of the BodyBuild series on the WEB.
http://math.mmu.ac.uk/Physics/Acorn/BB/BBindex.html
I just check and this particular article is not archived. Just mail Mike and
ask him very nicely if he could put up the relevant article. Ask him nicely
and I'm sure he'll get round to it. He's a busy man though. There is also an
article there about converting Atari joysticks for use on a BBC, this could
apply to the use of PC game pads / joysticks.

Mark Usher