Re: Mice and the IIgs

[spec@vax2.concordia.ca (Mitchell Spector)]

In article nathan@visi.com (Nathan Mates) writes...

>In article <3429C87C.7A6B@home.com>, Jeff Tacy  <slam@home.com> wrote:
>>>     First off you should really consider expanding the memory of this system
>>> to at least 1.25 MB (just populate the memory board inside with 256Kx1 chips
>>> which can be found for literally pennies these days).
> 
>>You mean the Apple IIGS memory expansion card accepts 256Kx1 memory
>>chips? That's
>>interesting...but are there any programs to test the real amount of ram?
> 
>   The Apple-made GS Memory expansion card accepts up to 3 additional
>banks of 256Kx8 (not x1; you need 8 of them to get 256K) in addition
              ^^
    When I say "256Kx1" DRAMs, I'm not referring to the number of chips
required to make up a full bank, but rather the actual bit density of 
the particular memory chip in question. The Apple IIgs Memory Expansion
Card does in fact use 256Kx1 chips (though your correct about needing 8
to get 256K in each bank). What you mean is 8 * 256Kx1 are needed.

    32 * 256Kx1 chips will equal 1024K, yet 8 * 256Kx4 chips will get 
you the same 1024K, as each chip is a higher density. You can also go
that route with 8 * 1MBx1 chips to get 1024K, as is the case on the
Apple IIgs ROM 3 motherboard. The same thing applies to the memory on
the Apple IIe motherboard. You have eight 64Kx1 chips to equal 65,536
bytes (or 64K). The IIgs motherboard use a pair of 64Kx4 chips to get
the same 65,536 bytes for the Ensoniq's dedicated DOC-RAM.

Mitchell Spector
spec@vax2.concordia.ca