Date: 2006-05-27 21:54:45
Hallo allemaal, I have my 1541LPT project working :) It hasn't been fully fool proof tested but it works. I can format a 'disk', save and load a one-liner and read the directory. And IMHO the rest should work as well as in fact I only altered the parts that are involved with writing to or reading from the floppy- disk. Some technical information: - one only needs to add a 6522 to the board and solder a 25 pin D-connector to the 6522. - I mentioned adding extra 2 KB of SRAM but you can forget that. At this very moment I'm only using TWO bytes of that RAM and IMHO it shouldn't be difficult to find a home for them in the first 2 KB. - At this moment the extra ROM part is 778 bytes big. The original format routine alone needs about 640 bytes and so, together with the unused 256 bytes at $C000, I could squeeze it in the original ROM. But that would mean no extra commands at this moment like "changing disk". - The PC runs a little Pascal program. At this moment it loads an hardcoded D64 image. It is not much trouble to alter so it will use a parameter to tell it what disk to use. There is a way to tell the 1541 that the PC has 'stopped' and started again. In this case the 1541 will reset as well. Future: - I first will optimize what I have at this moment. - Add some extra commands like 'change disk' - Maybe using G64 - Find out if I can find a place for all the routines inside the original ROM - Making a JiffyDOS version. FYI, the only part that my program affects is the format routine. -- ___ / __|__ / / |_/ Groetjes, Ruud \ \__|_\ \___| http://Ruud.C64.org Message was sent through the cbm-hackers mailing list
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