Re: Using slot 3 in an Apple IIe 1M

[Don Bruder <dakidd@sonic.net>]

In article <hfqv40h0l5uvo6am8g8vmkc0i7913uorei@4ax.com>,
 the8088er@sbcglobal.net wrote:
<Top post moved to where it belongs...>

> On Sat, 7 Feb 2004 14:59:11 -0600, "John Van Winkle"
> <appleiieman@charter.net> wrote:
> 
> >Hi all!  I have a non-PRODOS compatible clock card that I would like to put
> >in slot 3 and use since I am going to put a CFFA card in slot 7 (where my
> >time card is now).  I have read and heard about not using slot 3 if you have
> >the extended column card in the Aux slot.  I do have the RAMworks II card in
> >the Aux slot and nothing in slot 3.  My clock card is the Time II from AE.
> >But I do know that some time cards will work in slot 3.  what do you think?

> If theres something in the AUX port, no, Slot 3 will not function.
> 

While that's *GENERALLY* true, it's not QUITE completely accurate. 

A more technically correct statement would be that "If there's something 
in the AUX slot, no card *with ROM on it* will work in slot 3 'straight 
out of the box'." - The AUX slot takes over Slot 3's memory mapping when 
something is installed in it, which effectively locks out any ROM on 
whatever card is in Slot 3, which in turn pretty much means that 
whatever the card in slot 3 is, it won't be able to function unless it 
gets taken care of by external code. (For instance, it's completely 
possible to drive a Super Serial Card or similar with code you supply, 
completely bypassing the SSC ROM code, and making it possible to use the 
SSC in slot 3 along with an 80-column or RANWorks card in the AUX slot) 

As for you, John, there's a sure-fire way to find out if the Time II 
will function in slot 3 while you've got the RAMWorks plugged in: Plug 
it in and try it. It might not actually *WORK*, but trying it isn't 
going to do any harm to either the cards or the computer. I strongly 
suspect you're going to find that it doesn't work, since I believe the 
Time II has some clock read/set routines built into ROM on the card. 
However, I also suspect that it would be fairly simple to "transplant" 
the ROM code as I described above. Perhaps not a trivial task, but not 
exactly "rocket surgery" (as a friend of mine puts it) either. In my 
experience, the hardest part of the whole project is trying to shoehorn 
your "new" driver code into some corner of the machine where the OS or 
other things aren't likely to stomp on it every time you turn around.

-- 
Don Bruder - dakidd@sonic.net - New Email policy in effect as of Feb. 21, 2004.
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