The Commodore P-500, Commodore's 'Color PET'

See also Cameron Kaiser's Secret Weapons of Commodore Page at: p500

• Commodore Ultimax Game Console (a 4k version of the 'Commodore 64')
• Commodore 64 (you proabably have already heard of this model *wink*)
• Commodore P-500 (an intened upgrade/replacement for the PET users)
• Commodore B-128 (a business upgrade/replacement for the CBM 4000/8000 models)

Of those the most popular of course was the Commodore 64. The B-128 did reasonably as a business machine until larger systems (like the IBM PC) took the market. The ultimax was released only in Japan I have heard, and was not all that great. But this page is the story of the P-500, a cross between a B-128 and a Commodore 64.

From various sources I discovered the american P-500 was a casualty in bad planning. Commodore, wanting to get customers committed to buying the then unreleased B-128 and P-500s sent dealers 'demo units' (read 'beta test units') of the two machines for display to impress customers. These machines had not yet passed FCC (Federal Communications Commision) clearance yet, nor were they completely debugged. The problems began when some of the stores sold some of these demo units, and the FCC got wind that uncertified machines were being sold by Commodore. Of course the FCC got on Commodore's case and Commodore recalled all the units (except those that had been sold or those the stores refused to return.)

Sometime after that (I assume) Commodore found the 64 being popular (and cheaper than the P-500) and decided only to just release the B-128. I received rumors the other recalled P-500s were 'bulldozed' (i.e. ran over by a bulldozer to make them truly scrap); regardless all that remain in the U.S. are the few out on the streets and probably a couple former prototypes.

In Europe the P-500 faired a bit better as there are many more around, but I assume did not have much of a market as there is virtually no software for the unit.

This particualr P-500 has obviously preliminary ROMS as it starts up with a white screen and cyan border and the startup message:

 
*** commodore basic 128, v4.0 ***
 
 
ready.

beyond that, I have not explored much of it as either a RAM or RAM controller chip is keeping me from getting useful BASIC results.

The B-128/P-500 features:
• 6509 Microprocessor
• 128 k of RAM (utilizing bank switching like the C-128)
• a true RS-232 C serial port
• IEEE-488 peripheral port (like the PET/CBM computers)
• Cartridge Port
• Full size keyboard with 15 function keys and neumeric keypad.
• An 8088 coprocessor board expansion bus. (which could run CP/M 86)
• An internal power supply (which sure runs hot).
• 6581 SID sound chip (just like in the 64)
• Datasette port (though the B-128 ROMs has no code to use it)

• 80 column B & W video output (6545)

• 40 column VIC-II video output (like in the 64)
• Two joystick ports
• ROM routines supporting the datasette (absent in the B-128 series ROMs)