Hi, I don't know if it's the same board but it looks similar I think there were a sort memory in $9000/$A000 to communicate With the cpm board. Perhaps with a jumper to choose between both I had 2 8050 disks, one was a standard cbm disk with A program, a large part of basic and a small part of 6502 assembler In fact, apparently, the cp/m bios was redirected to the 6502 - signaling with the PIO - memory block (I can't remember where) - a small 6502 assembler program charged of the transfers - then a "quite" large basic program was processing the bios request - then the small assembler program sent the response to the request. It was also probably possible to map some sections of the cp/m memory Into the 6502 address space ($a000 ???) To boot the cp/m board board was probably using the following scheme - z80 stopped - cp board loaded block by block with the cp/m code - z80 started I don’t remember the details on how the pio worked. I'm not sure if it was with this board but I think that the cp/m disks Where stored in cbm files. I worked a few days with this board, trying to attach a hard disk driver But when I saw how dirty the software was we just stopped using it. Perhaps that the 24 pin socket was for a numeric processor -----Message d'origine----- De : owner-cbm-hackers@musoftware.de [mailto:owner-cbm-hackers@musoftware.de] De la part de Ruud@Baltissen.org Envoyé : mardi 17 novembre 2009 18:36 À : cbm-hackers@musoftware.de Objet : Re: info cpm board for cbm 8032 Hallo Didier, As promised: http://www.baltissen.org/images/z80card.jpg The unpopulated socket is meant for a 6502. As the you can see there is no EPROM onboard. The unpopulated 24 pins socket is NOT meant for an ERPOM. Pin 1 and 3 are connected to ground, pin 12 isn't. Pin 2 is connected to +5V, pin 24 isn't. I have no idea at all what could fit there. The Z80 communicates with the 6502 through the 6821/PIO combination. And even there are anomalies; the pins are connected to each other in a weird way (or I did something wrong). That rules out that the Z80 could address the $A000 expansion for example. -- ___ / __|__ / / |_/ Groetjes, Ruud Baltissen \ \__|_\ \___| http://Ruud.C64.org Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2009-11-17 20:00:11
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