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Re: Apple II VGA video card and the IIgs



>Does the IIgs use the same mechanism as the IIe to access the memory in
>banks beyond the first 64k "bank 0"?

there is 128k of RAM on the IIgs motherboard that is used for IIe
emulation.

>Or, given that it has a 24 bit address space there are not "64 banks" to
>shuffle in and out but a contiguous memory map instead and no
>softswitches to set ?

you have to set softswitches to get into the proper video mode...

I've looked at 65816 code and never wanted to study it.


>Another way of making the same question is: The IIgs specific video
>modes are accesible while the IIgs is in Apple II compatible mode of
>operation (if such a mode exists, I think it does) ?

There are AppleSoft & commands that will allow you to draw on
the IIgs video mode screens.

>And if the memory map is not fragmented in banks, is there any chance
>for a card sitting in a slot to guess somehow about the missing a17..a23
>address lines ?

through the memory expansion slot

>Is there IIgs-specific slot in the IIgs that is different from the Apple
>II slots ?

the memory expansion slot is IIgs specific

>And, the Apple-II-like slots in the IIgs are identical to the real Apple
>II slots or not ? If not, what's the difference ?

same slots, 16 bit address, 8 bit data