Hi! Holger Busse sent them to me, I scanned them and Marko has put them online: The C500 schemtics! This machine is (in germany) known as CBM500, similar to the CBM600 and C700 machines. The schematics say "PET-II" and "P500". The whole machine is similar to the CBM-II (C600, AKA B128): - it has 128k or 256k RAM (located in bank 0,1 or 0-3) - it has a 6509 CPU with its banking scheme (esp. the I/O in bank 15) This machine seems to have quite some oddities: - it has a VIC-II and thus runs at 1MHz - The VIC-II has access to 1k/8bit of video RAM and 1k/4bit of color RAM and a fixed 4k charrom. - However, there is a special 64k RAM bank that is "powered by VIC". From the FPLA equations that come with the schematics it seems that by setting special output lines (CA and CB on the IEEE488 TPI) one can make the VIC use this 64k bank, that seems to be located in bank 0. This seems to be useable for hires graphics. Have fun! Andre -- Email address may be invalid. Use "fachat AT physik DOT tu-chemnitz DOT de" ------Fight SPAM - join CAUCE http://www.cauce.org------Thanks, spammers... Andre Fachat, Institute of physics, Technische Universität Chemnitz, FRG http://www.tu-chemnitz.de/~fachat - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tcm.hut.fi.
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