Re: B500??

From: Cameron Kaiser (
Date: 2002-07-07 18:31:28

> I'm still wondering what a B500 really is. How does it differ from the
> Commodore P500 and especially the 600 models? I've of course read the SWoC
> pages, but they are not very clear about this machine.

That's because I'm not very clear about it either :-) We sat down with your
picture of the 600 series board and Steve Gray's picture of his B500 and
compared them and the boards are nearly identical, as you say. The only thing
weird on my unit is that 5-pin video port. That's the only thing that seems
to distinguish this as a 500 at all.

> Is it possible that the B500 is a 600 with just 1MHz clock? Or are there other
> differences? And, while I'm asking curious questions: Is the 1MHz clock rate a
> proven fact, or a rumor?

This is one major reason I'd like to restore this unit to at least see what
the differences are. The board crystal says 1.843200 and the oscillator
crystal says 18.000. How is this compared with the 600 and P500?

> Does anybody know where to download the kernal ROM for a B500 from the net for
> comparison purposes?

Unfortunately, all I seem to have here is the PLA and char ROM. :-(

Larry, since you asked about solder pads for the joystick port, I didn't
see anything obvious rear left. It is completely dissimilar to the layout
of the P500 Steve Gray has. Looking at his picture of the B500 and P500
side by side, this is clearly a B-series board. It would seem logical to
assume this is a 600, but the 5-pin video port is a 500 feature.

However, I do have a connector "P1" where the joyports should be. Does this
connect up to your joyports on the P500? On this board, it's top left.

----------------------------- personal page: --
 Cameron Kaiser, Point Loma Nazarene University *
-- Eat healthy, stay fit, DIE ANYWAY! -----------------------------------------

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