> I've picked up a couple of Commodore units, and I don't know much about
> them. I'm not really a home micro person, so I am a little out of my
> depth here...
> The first is a P500. I have the schematics, which also call it a PET-II.
> It's a 6509 (6502 + paging registers for 1M of RAM) based machine. Video
> is a VIC-II, sound is a SID. There's 128K on board. BASIC/KERNAL is 3
> EPROMs in a cludge-board on top of the ROM sockets. Rear panel connectors
> are 2 joystick ports, IEEE488 (presumably for disk drives/printers/etc),
> cassette, sound (RCA socket), RS232 (DB25, and there's a 6551 on the
> mainboard), video out (8 pin DIN, like a C64), cartridge (again like a
> C64) and mains in
Wooooohaaaaaaaaa!
So I'm no longer aloone with mine :)))
> Questions :
> 1) Is it worth adding the extra sockets/chips for the next 128K of
> memory? Will BASIC recognise it?
Jep, it will, but the additional memory isn't realy usefull in basic.
The Programm code has still to reside in the programm bank.
I would suggest you DONT add them - if you like to have a P500-
alike machine to play (and rebuld :), I would love to give you
a CBM 610 (B128) in exchange for the P500 (only minimal differences,
in fact the 6xx are 'production' versions of the P500 - so less
bugs (but still buggy)). There are even two (German) Books about
the 5/6/7xx machines including some in depth technical informations.
> 2) Any references on programming this thing? It appears you can program
> it so the VIC accesses one of the 64K DRAM banks rather than the 1K video
> RAM (+ 1K*4 colour RAM). Anyone know how to do this? What about sound - I
> guess I have to poke the SID directly.
Jep, but there has been also some libraries and basic extensions.
Servus
Hans
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Ich denke, also bin ich, also gut
HRK
Received on Fri Jun 18 1999 - 12:51:23 BST