Re: Question: Hardware differences between Unidisk 3.5 and 3.5Drive?

["Mark Cummings" <NOTfigjams@primus.com.au>]

> I have 2 UDC cards, the Laser UDC  card which wouldn't use the 3.5"
>UniDisk while the vtech UDC card would.  While the card designs are
>very different but because the ROMs are interchangeable I'd suspect the
>same manufacturer. I'd suspect that 3.5" UniDisk support was dropped
>somewhere along the line because if you were going to get the 3.5"
>UniDisk drive, you could get the Apple controller card for only a bit
>more when packaged with the drive.  If you bought the UDC card you
>wouldn't likely choose the 3.5" UniDisk to use with it since Apple charged
>twice as much for their drives.


Now I'm confused, my UDC card has LASER UDC on the EPROM and VTECH printed
on the circuit board. I think it is a late model as there is a VLSI surface
mount chip on it.
The instruction leaflet has Laser Computer on the front.
A quick check inside it does not specify that it can't use Unidisk 3.5, but
it does say Apple 3.5 drive as one of the drive options.

So do I have a Laser UDC or a VTECH UDC ?

>One problem with many UDC cards is with the eject button on the Platinum
>3.5" drive. Mostly the second drives eject button didn't function and in
some
>cases neither button worked. I ended up wiring the eject button directly to
the
>eject mechanism in the 2 drives I use with a UDC card. A possible problem
>with that mod is that the drive will now eject while in use. Maybe I'll try
>that
>sometimes just to find out just what happens.


Ahhhh, I noticed that the eject didn't work on the 1st & 2nd Apple 3.5, I
thought it may have been a fault in the drive daisy chain board, as I have a
couple that don't daisy chain too well.

Mark