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

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

As it happens I do have an EPROM burner.
I'll check out the symptoms again 1st, just to make sure.

Mark
(remove NOT from e-mail)


Wayne Stewart wrote in message <3ABCD540.9075F7E9@intergate.bc.ca>...
>
>
>Mark Cummings wrote:
>
>> 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.
>
>Interesting. I have the card that appears to match your description(7 chip
card
>about 6"
>long?) except it doesn't have VTECH on it anywhere. I t did have Laser on
the
>EPROM
>and in the EPROMs code. All the chips on it have a 1988 date on them.
>I have an older UDC card in storage so I can't check the exact specs easily
>with about
>35 chips(no surface mount ones) and VTECH printed on the board. I seem to
>recall seeing
>1986 production chips on it and thinking they likely beat the IIgs into
>production.
>
>
>>
>> So do I have a Laser UDC or a VTECH UDC ?
>
>I guess both then. I suspected the same manufacterer of my cards given the
>EPROM
>compatibility. Sometimes it's awkward making statements based on a couple
of
>hardware examples.
>
>> 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.
>
>On my laser UDC card the first works but not the seconmd. If you have a
burner
>that'll do 2764 EPROMs and feel like seeing if an EPROM change will get the
>first drives eject button going I can email you the image
>
>    Wayne
>
>