Re: Apple IIgs ROM question

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

Justin Scott <djnospamimpakt.net> wrote:

>Mitchell Spector <a_specto@alcor.concordia.ca> wrote:
>
>>    Not at all, though there are some minor advantages (none of
>> which added any further functionality or features however, it's
>> merely a cleaner/more efficient redesign of the original board).
>> I just posted the differences about a week back, it may still be
>> available on your newserver (if not, use Goggle/DejaNews).
>
>I'll have to dig that up, it sounds like good reading.  I never had a IIgs (I
>have one on its way to my house via USPS right now).  I always wanted one.
>For some reason, I seem to remember there were a few things that you couldn't
>do without a ROM 3 board, but that may have just been because the other boards
>didn't have enough ram by default. <shrug>

    Nope. There was definitely not any software that was ROM 3 specific
(I suppose a programmer could have added a firmware check to prevent
his/her software from running on non-ROM 3 boards, but then why would
they?).

    As a matter of fact, Apple never offered an upgrade to the newer
board and claimed you could bring your ROM 01 up to the same
level by installing 1 megabyte of RAM and running System 5 or 
later.

>>    It is only necessary to upgrade if you have the original ROM 0
>> firmware--it was a simple chip swap upgrade Apple did free for a
>> number of years (for those IIgs's released between September 
>> 1986 and August 1987). Even then, this is assuming your using
>> a IIgs to run its native 16-bit software.
>
>The system I've purchased is actually one of the //e->IIgs upgraded systems.
>This system had (from my understanding) a different motherboard than the other
>systems.  It includes a connector for both the //e internal keyboard and the
>optional //e keypad.

    No really. Many of those so-called IIe upgrade boards were shipped
in standard Apple IIgs cases. Most Apple IIgs boards did not have the
connectors in place, but there were solder pad locations to add the
pin connectors if you wanted to do it.

>This upgrade package was short lived, and I don't think they made a ROM 3 
>board with //e keyboard/pad connectors.

    Support was completely removed from all ROM 3 boards (no connectors
or solder pads present). Oh, one other difference I forgot to mention
about the ROM 3 is the IIe mouse card with Mac 128/512/Plus style
serial mouse, is not supported under GS/OS. On previous machines it
worked under both GS/OS and ProDOS-8.

    Support was removed from the ROM 3 because the IIe upgrade was
no longer an option. At any rate, I can't imagine someone wanting to
waste a slot AND use that mouse which was like a big bar of soap. :)

>In the case that this system is a ROM 00, you're saying I could take the ROM
>from a standard ROM 01 machine, and swap it, and the //e upgrade would be a 
>ROM 01 machine? :)

    Yes. The original Apple IIgs motherboard accepted either the ROM 00
(1986) or ROM 01 (1987) firmware chips. Once the latter was released,
support for the ROM 00 was dropped by Apple and any programmer 
writing software for the machine. 

Mitchell Spector
a_specto@alcor.concordia.ca