Re: Questions from a newbie

From: Marko Mäkelä (
Date: 2005-01-27 22:07:20

Hi Jordi,

Welcome to the club! If we were in the 1980s, I might start a flame war
about you collecting z80 equipment. :-)  Just kidding: also Commodore has
used the Z80 in the C128, and maybe the Z8000 in the C900.

> However, the 8296 is one of the most beautiful machines I've ever seen!

Hmm, does your 8296 have a separate keyboard, or is it integrated?  I like
better the PETs with separate keyboard, that is, the CBM II series (a.k.a.
500, 600 and 700 series) and the CBM 200 (a.k.a. 8032-SK) and CBM 220 (a.k.a.

> Thus, I would like to know more about this machine. If you
> do not mind, I will list some questions. If some (or all)
> of the questions are too elementary for this list, please,
> accept my apologies and I'll try to find this info somewhere
> else.

No, I don't think it's too elementary.  You can find some schematic
diagrams and documents at, but it may
be hard to get a general idea from that kind of reference material.

> - After turning the machine on, it says that it has 32k available.
> But there are webpages that say that the memory in the 8296
> amounts to 128k. Are the 32k available only to BASIC and the rest
> of the memory to machine language (of course, I know only 64k can be 
> addressed by a MOS6502, but I assume some banking mechanism)?
> or the 128k were an upgrade to the basic configuration?
> I've not opened the 8296 (yet), so I don't know if my machine
> has 128k.

I'd like to know the answer too.  How is the extra memory accessed?
Is the mechanism same on the SuperPET?

> - I would like to program the 8296 in assembly language,
> using the 8296 (not a cross-development system). Is this
> possible? I am used to the typical edit-compile-run-crash-...
> cycle but that assumes the existence of an editor, 
> an assembler, etc.

Back in the 1980s, I programmed the C64 (my first computer) using a
machine language monitor built-in non-symbolic assembler.  I didn't
even have a printer, so I wrote the addresses of subroutines by hand
on a piece of paper.  Sometimes I had to make room for a routine by
moving blocks of code to different addresses.  The monitor I used had
a 'T'ransfer command for this, but I had to fix all absolute jump
addresses afterwards, one by one.

On the PET, you can bring this to the extreme.  There is a built-in
monitor, but it doesn't feature a disassembler or assembler.  There's
just 'M' (memory dump) and ':' (write to memory).  If you were used to
reading 6502 hex code, you could write simple programs using those two
commands.  A couple of years back, I read the hex code of the 8032
reset routine.  I wanted to find the subroutine that makes the sound
when the computer starts up.  I managed to find it, and I wrote a
program that calls this routine in a loop. :-)

More seriously, I think that there may be some assemblers for the PET
that use the BASIC interpreter as an editor.  There are several such
assemblers for the Commodore 64.  But it's infinitely more convenient
to use a cross assembler.

> - Finally, let's assume I find the software I need in the web.
> What is the most usual/practical/simple method to transfer a
> CBM program from a PC to a CBM-formatted disk? I've heard of
> some methods (X1541 with StarCommander, C2N232 cable, etc.)
> but I would like to know which one is the simplest.

I'm the author of the C2N232, so you do not need to believe me when
I say that the C2N232 is the simplest.  But it is: just type LOAD
and invoke c2nload on the PC.  There are no moving parts or no catch-22
situation (bootstrapping the transfer program).  I have written a
summary of transfer methods at

There are some plans to manufacture the C2N232 again.  I made 130 of them
in 2002, and I sold the last ones last year.


       Message was sent through the cbm-hackers mailing list

Archive generated by hypermail pre-2.1.8.