C4P floppy issues

From: Bill Sudbrink <wh.sudbrink_at_verizon.net>
Date: Thu Sep 23 21:12:48 2004

> A friend gave me his first computer to go in my collection.
> Its a Challenger C4P. I do have the original manuals etc.
> And of course my friend for information.
>
> What I am looking for however is additional information,
> websites etc devoted to it. I have the cassette based
> version. The first question would be details on the
> floppy disk version. IE can I upgrade mine. If not,
> sources for programs for the cassette based unit.

You might think that you could just add a floppy interface
board and have a C4P-MF. Nope, afraid not. The floppy
controller is integrated into the CPU card in the C4P-MF.
That CPU card is a 505. On a non-MF C4P, the CPU is a 502.
On the 502, instead of the floppy interface, there is Micro$oft
8K BASIC in ROM and the cassette port (the C4P-MF does NOT have
a cassette port). One possibility to get cassette functionality
on a C4P(non-MF) would be to hack up a 470 board... but you
would then also have to re-do the monitor ROM, as the boot
loader code in the C4P monitor (according to rumor) doesn't
work anyway. Might have something to do with addressing conflicts
with the cassette port. Finally, there are issues with the
OS (usually OS-65D) expecting/not expecting to see BASIC in ROM.
I think if it sees it, it figures that it is running on a C1P
and you get funny results if you are not (keyboard issues maybe?
I'd have to look through some old PEEK65s to check).
Received on Thu Sep 23 2004 - 21:12:48 BST