Re: Apple 1 replica is almost finished

["Vince Briel" <vbriel@comcast.net>]

>     I like your Apple I project.  It would help us to learn Apple I that
is
> really in history.

That's my purpose. Most people including myself have never seen an Apple 1
in person, let alone one running.

 If you have all original software on tape, I would
> recommend that you make backup cassette tape so we can experience by
loading
> software from tape using 256K ROM.

I don't have the tapes, but they have been copied to wav and mp3 format.
Once I recreate the cassette interface we can move them to plug in eprom
boards.

>     I see that expansion slot has pin 13 for A000-AFFF, pin 22 for
> C000-CFFF, and pin 32 for B000-BFFF.  Please explain how they work because
> they are not the same as Apple II expansion slot.

Correct. Unlike the Apple 2 (pulling out my ref manual now) there was no
such thing as slot specific addressing. Those address ranges are available
in expansion with those lines coming off of an address decoder. So, if you
wanted an EPROM at A000-AFFF you would tie pin 13 to the CE line of the
EPROM. So, with the II's the system needed to know which slot to address
when doing like a pr#6 command. With that command it knew exactly which
memory location to jump to to start up the card in that slot. This
eliminated memory conflicts and other issues. The memory the card used in
the system depended on where the card was installed. Sometimes this became a
problem for programmers causing the cards to be slot specific. I could have
my facts a little off, please correct me if I'm off base here.



>     If you have Star Trek high resolution with only black and white using
> video controller card to Apple I expansion slot, it would be great to
> replica, but I do understand that Apple I does not support graphics.

No graphics, no screen control. Very early form of TV text. Scrolling text
only with no up/down cursor control. Basiclly like having a printer for a
screen.