Re: Another mystery card (to me at least)

[brian-list-member@rogers.com (Brian D.)]

Robert Flossmann <rfka01@gmx.de> wrote in message news:<MPG.1b9561f6a3d28e9a989680@news.individual.de>...
> Hi all,
> I got one obscure apple II card off modern day's dump heap (ebay):
> 
> The link to the picture is is: 
> http://www.speedsurf.to/bertl/mystery.html
> 
> The bigger ICs (of which two are missing) have the number: hm6116LP.3
> 
> Do you know this card? What do the DIP switches select? Do I have to add 
> the two missing chips before using the card?
> 
> Thanks Robert


Hi Robert;

The card you have is a 16k EPROM/CMOS memory expansion card. It was 
manufactured by IBS Computertechnik in 1984. The catalog product number 
was AP8.

The card can use the CMOS memory chips that are installed on your card, 
or EPROM chips for user programs. The three batteries allowed the CMOS 
to be used as permanent (as long as the charge lasted) storage.

The 16k is in parallel to the ROM and I/O area and is overlayable with 
the use of bank select softswitches. The address space is divided into 
four areas that can be individually selected. There is also an autostart 
function so you could boot from the card on power up.

I think I have the schematic for the card in my A2 archives. If you 
would like, I can check.

Cheers,

Brian

<badavis@no.spam.rogers.com>