PS/2 Interface (was: Wang 300 Calc]

[Tony Duell]

> 
> On Monday 17 September 2007 18:57, Tony Duell wrote:
> > > When I think about it, the MITS 8800 had connector punchouts for DB25
> > > *only* in the back panel.  DB25 seemed to be the lingua franca back
> > > then for hobbyist interfaces.  If one had an 8" floppy drive, one ran
> > > the ribbon cable right through the crack between the back panel and
> > > the case cover directly to the controller card(s).  No DD50s.
> >
> > I have an S100 amchine called a CASU Super C. It contains a Cromemco CP=
> U
> > board, some other stnadard 64K RAM bvoard, a Micromation Doubler disk
> > controller and CASU-designed boot ROM and seiral interface boards.
> >
> > The disk drive (a Persci) is in a separate box. The 50 wire interface
> > cable is split down the middle adn connected to a pair of DB25s...
> 
> I have a Cromemco "System 3" (?).  It also has a Persci drive in it,  a d=
> ual. =20
> Is that what yours is?

My machine is clearly not a Cromemco anything. The cases (separate box 
for the drives), PSUs, backplane and some of the boards are made by CASU 
in the UK

But yes, my Persci drive is a dual-disk unit. 4 heads on a voice coil 
positioner. And motors to eject the disks. 
 
> There's apparently some sort of a problem with mine,  as the floppy which=
>  was=20
> in it when I got it had been tried so much and for so long that the initi=
> al=20
> tracks were completely worn away,  and you could see through it.
> 
> On perusing the service data for it,  I notice that the drive uses a bunc=
> h of=20
> _incandescent_ light bulbs for things like index sensor,  etc.  I would=20
> imagine that one or more of these is likely to be the problem.

Possibly. Typically with a problem like this I hook up the drive 
exerciser and see just what the drive is, and isn't, doing. 

-tony