Re: Laser UDC Documentation

["Henry" <apl2research(.a.t.)comcast.net>]

Hello Steven.

Funny you should mention two different ROM versions.  We originally started 
to research this card to clone.  I have both versions of the card - the 
'old' full length that said 'VTEC' on it, and the 'new' short card with the 
QFP on it, like David mentions in his post.

I had several 'old' versions of the card and since it was all standard glue 
logic, it was a prime candidate for our first CPLD project which we later 
decided on experimenting with the Rev. C SCSI controller.  We then decided 
not to clone the controller since it looked like the Apple 3.5 Drive 
Controller was possible.  Since it did more, we went that route.  Anyway... 
before we dropped the project I had found that a one 'old' style controller 
had different ROM code in it, which I thought was odd.  We did some further 
testing but never determined what the difference was between the two ROM's. 
You know?  Maybe the 'patch' David spoke about?

One nice feature of the controller was if it didn't find a disk in a 5.25" 
drive it would 'skip' to the next available boot device as the IIgs does 
when it's set to 'Scan' mode in the Slots menus.  I know Bill was looking in 
to a 'skip' mod for the Disk II Controllers when we decided to look at the 
UDC card.  I believe the Apple 3.5 Drive Controller will also 'skip' drives. 
Anyway, we never did determine what drive combinations were possible on the 
UDC.

I was also going to make up some drive cables for the UDC and list them in 
the Store.  I know how rare they can be.  Does anyone have the pinouts? 
Bill now has the cards and he's been quite busy and hard to reach these 
days.


-- 
Henry S. Courbis
www.GSE-Reactive.com
Apple II Series Legacy Hardware - Come take a look at what we have to offer!


"Steven N. Hirsch" <shirsch@adelphia.net> wrote in message 
E-ednb-r0tOvK-TZRVn-vg@adelphia.com">news:E-ednb-r0tOvK-TZRVn-vg@adelphia.com...
> Warren Ernst wrote:
>> Though it was supposed to work, I *never* got an Apple 3.5" drive (the
>> platinum the GS uses) to work with an enhanced //e with the Laser UDC.
>>
>> I *did*, however, get the older-style 800k macintosh 3.5 drives
>> (without the eject button) to work with it, which was kind of neat.
>>
>> If there are any diagnostics, you would access them the same way you
>> would on any card. Get a Basic prompt. Go into the Monitor (call-151).
>> Then type Cx0AG where x is the slot number the card is in.
>
> There are at least (2) distinct ROM versions for the UDC controller.  On 
> of them supported the Unidisk 3.5 (original Apple 3.5" drive for IIe and 
> IIc) and one supported the later Apple Disk 3.5.  AFAIK they are 
> interchangable on all the UDC hardware levels.