Re: Sockets

["Roger Johnstone" <rojaws@mac.com>]

In article <3B89C08B.237387A7@intergate.bc.ca>, Wayne Stewart 
<waynes@intergate.bc.ca> wrote:

> David Empson wrote:

>> Wayne Stewart <waynes@intergate.bc.ca> wrote:

>>> I was thinking that since the ZipGS doesn't actually need to be in a slot to
>>> run, then everything is coming through that cable plugged into the CPU
>>> socket.

>> Almost everything comes in through the CPU socket.  The ZipGS does use the
>> slot connector to handle DMA accesses.  It might also use some of the clock
>> signals and get power from there.

> I might easily have not noticed lack of DMA as the time when I was running it
> out of the slot was when I was experimenting with upgrading.  Had it lying on
> its back on a piece of cardboard so it'd be easier to  swap some parts in and
> out. Got the idea from a posting by Tony Diaz. I believe I ran it for a couple
> of hours total that way.

There was a version of the ZipGS which fits into the CPU socket. Checking an
ad from Zip Technology, they were advertising the model 1500 (ZIPChipGS),
1525 (ZIPChipGS Plus) and 1600 (ZIPGSX).

The 1500 was the CPU socket version with an 8MHz CPU and 8KB cache. It
wasn't DMA compatible. The cache chips were surface mounted on the board.

The interesting one is the 1525 which was the same as the 1500 but with 16KB
of cache. It was supposedly DMA compatible, but it still just plugged into
the CPU socket.

The 1600 was the full size card which had socketed cache chips and the
expansion connector, plus extras like DIP switches and activity LEDs.

--
Roger Johnstone, Invercargill, New Zealand

Apple II - Future Cop:LAPD - iMac Voodoo2 - Warcraft II
http://homepage.mac.com/rojaws
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