Re: Downgrade Apple //e?

[steve@dosius.zzn.com (Dosius)]

"Bryan Parkoff" <BParkoff@satx.rr.com> wrote in message news:<nu2dnQbOoIPQ0xOjXTWQkQ@giganews.com>...
> I have unenhanced Apple //e that displays "Apple ][" at cold start.  How
> do I read "revision A or B" on the motherboard?  How do I downgrade
> unenhanced Apple //e that it does not support double resolution?  I mean to
> switch from Revision B to Revision A.  Can you explain how the revision B
> was fixed to enable double resolution?  Is it because of fixing 80 column?

You really want to disable DHGR?  That's a bit, ahem, strange, IMHO,
but...

>     Will MouseText be supported on unenhanced Apple //e if Character ROM is
> swapped?

Not properly; running the unenhanced ROM on emulators that do
MouseText will show that MouseText is printed at times that it
obviously shouldn't be.

>     It looks like that Apple II+ does not have double resolution support
> because it does not have softswitch for double resolution, but unenhanced
> Apple //e does have additional softswitch.  Is it possible to program double
> resolution on Apple II+ without needing to use softswitch?  

Not AFAIK.

> I have 128K and
> 256K language card.  I believe that it is Saturn.  If it is not possible,
> 6502 has no way to switch between high and double resolution without using
> softswitch.  Is it true that 6502 requires softswitch so 6502 would be able
> to manipulate the hardware through softswitch.
>     Why is softswitch built?  Why can't 6502 can do without it?

6502 doesn't have port-based I/O like the Z80 and 8086 have, so it has
to be done through the memory map.

-uso.