On Tue, 20 Jul 1999, William Levak wrote: > On Mon, 19 Jul 1999, [ISO-8859-1] Marko Mäkelä wrote: > > > On Sun, 18 Jul 1999, Bo Zimmerman wrote: > > > > > Have no idea what they are. They just appeared to be EPROMS on the 8280 > > > motherboard. I noticed funet didn't have them... so here you are! > > > > Thank you! I assume that this is the 8" counterpart of the 8050/8250. The > > ROM dumps are now available from > > <URL:http://www.funet.fi/pub/cbm/firmware/drives/old/8280/>. Any > > additional information of this drive is welcome (e.g. a parts list similar > > to the file .../8050/README). Were these all the ROMs on the motherboard? > > > The message in the 300543-001 ROM identifies it as Cbm DOS 3.0. > 300543-001 appears to be $E000-$FFFF. > 300542-001 appears to be $C000-$DFFF. > They are similar to DOS 2.5 and 2.7. > > 300541-001 is different than the GCR ROM in the other CBM drives. It also > does not appear to contain 6502 machine language. > > Somewhere in the ROMs should be a table giving the format (tracks and > sectors) of the disk. I have gone through the ROMs thoroughly. The section of the ROM that should contain the format parameters contains $AA characters instead. The same for the section that should contain the directory parameters. This would suggest that the drive is using a standard controller chip, perhaps a 1791, 1793, 1797, 6591, or 6843. These would have been available and are compatible with 6500 systems. The buffer setup table is present and is identical with the 8050 table. This means the RAM is identical with the 8050. - 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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