Re: Your first A2.

[a_specto@alcor.concordia.ca (Mitchell Spector)]

markREMOVE@a2central.com (Mark Percival) wrote:

>a_specto@alcor.concordia.ca (Mitchell Spector) wrote:
>
>>    Your right, I just did a little digging and found Apple even had
>>official part numbers for II Plus systems that shipped in the three
>>RAM configurations. I don't know why, but I thought I remember
>>48K being standard then. Thanks for the correction.
>
>Steven Weyhrich makes mention in his Apple II History that the Apple
>II plus came standard with 48K RAM.  I know from what I saw that this
>wasn't true until the later run II pluses in the 1981-1982 era.

    Ah, that's where I probably remember that from (I read most of
those chapters back in 1992). I just went and had a look again
and it isn't in error, just not carefully worded...

Taken from the Apple II History files, Chapter 6:

"With the decision made to upgrade the Apple II, other changes were
made to make it more attractive to new computer buyers. The cost of
RAM chips had dropped considerably, so [most] new II Plus systems
came standard with a full 48K of RAM."

    The key word there to watch for  is _most_ new II Plus systems,
not all. A few paragraphs down is a better indication--an Apple
packing list that lists different RAM configurations that could 
be ordered.

>>    They did remove support for 4K DRAMs though, right? Or was
>>that just the jumper blocks to select between 4K and 16K chips
>>that I'm thinking of?
>
>This is also mentioned in Apple II History but again this didn't
>happen until the later run II pluses that they remove the jumper
>blocks.
>
>See http://www.apple2history.org/history/ah06.html, 2nd paragraph.

    Hmm, flipping through Jim Sather's Understanding the Apple II book
(and refreshing my memory here, no pun heh) the revision 4 motherboard
was the first to eliminate the 4K DRAM option, as 16K jumpers were
soldered in instead of being socketed.

    There's no specific mention of which revision boards were used in
the first Apple II Plus's. Probably something between revision 4 and 7
if I had to guess. It's very conceivable II boards were used for early
II Plus cases as the only functional different, for the most part, was
the replacement of Integer ROMs with Applesoft ROMs.

>Another feature of those late run Apple II pluses was the modification
>to the keyboard that made reset a ctrl-reset to help prevent
>accidental resets.  There was a switch that disabled this under the
>keyboard.

    Actually, according to Jim Sather's book that keyboard change took
place at approximately the same time as the II Plus introduction.

    One of these days I need to repair my 1978-vintage Apple II
keyboard. There were several loose wires soldered on the underside
which I inadvertently removed, figuring they were a user modification,
but doing so caused the keyboard not to work. If I knew where to
reconnect the wires, it should come back to life.

Mitchell Spector
a_specto@alcor.concordia.ca