ScuzzBlog: Diaries December 2019
Entry 5th December 2019: Post 01: Amiga A2000 1MB RAM CARD.
Amiga A2000 1MB RAM CARD.
So what were you doing in 1986. More specifically the 49th week of
1986 or maybe the first week of 1987. Could you have been in Korea,
USA, Portugal or Germany. So long ago and so many countries and all
to provide the Amiga 2000-A computer with it's 1MB RAM card. Just
1MB and not even that as half of it was unpopulated. The card came
with 512 KB RAM soldered to the board ( 16 DIPs) at 150ns. There
are 16 additional DIP sockets that accept another 512KB RAM giving
1MB total.
The board is jumpered giving differing configurations:
512KB system RAM
Kickstart RAM
1 MB system RAM
Kickstart RAM + KB system RAM
And all this and the card connects to the CPU slot.
The question I have ... is why the modification. Each card I have
seen including the one I have has wired modifications to the rear.
There is clear indication of severed tracks, and very crudely disabled.
There are three socketed chips all from Germany.
This card is an enigma in truth. It was originally designed for
the German A2000 Model A versions to be fitted to the MMU slot
also known as the CPU Fast Slot in the US designed A2000 machines.
Interestingly the card may not work with the Model B and C A2000
computers. What intrigues me is the age of this card .. given
that the Amiga 2000 was released in March 1987 and the chips on
this card predate the release of the Amiga 2000.
I find it hard to believe that a new computer would come with a
card with obvious modifications. Unless each and every card I have
seen was modified to work with all Amiga 2000s. Sadly I cannot
find any information on the reason for the modifications. That is
why I ask what were you doing back then. Maybe you have a card
that hasn't been modified... or not. Wishful thinking.
The Amiga Hardware Database
From the Big Book
PS: The card is clearly labelled 1986.. predating the Amiga 2000.
Jumpers for goal posts: From the BIG BIG BOOK
[Jumpers]
The description refers to the jumpers labelled left to right, with the pins labels as followed:
2 4 6 8 10
| | | | |
1 3 5 7 9
For 0.5 MB of RAM, the following pins should be connected:
3 & 4
5 & 6
7 & 8
For 1MB of RAM:
3 & 4
9 & 10
For Kickstart RAM:
1 & 2
5 & 6
7 & 8
For Kickstart RAM and 0.5MB RAM:
1 & 2
9 & 10
Amiga A2000 1MB RAM CARD.
Amiga A2000 1MB RAM CARD.
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