Motorola EXORciser M6800 System

osi.superboard at gmail.com osi.superboard at gmail.com
Tue Jun 5 16:10:24 CDT 2018


Since a few days, my EXORciser Development System is finally able to boot from floppy diskettes.

Previous attempts have shown that the Motorola EXORciser M68SFDC1 floppy disk board used has a special modified ROM version. This was probably written for an 8-inch drive, in which the Write protect and Direction signal were inverted.
For the sake of simplicity, I have used free inverter on the board to invert the signals accordingly.
After adjusting the PLL frequency, reads and writes from the card are now error-free. And all without FDC, only clever programming by Motorola software engineers in the early 76’

Originally, the EXORdisk system was a dual drive with two 8 "units. This I have replaced with a double drive of two 5.25 inch units. An Epson and a TEAC, which can be jumpered to 360 rpm. Luckily, 2HD floppy disks are easy to R&W.
I also got a GOTEK floppy emulator running, which I can boot from. Thanks to Roland Huisman, Bitsaver has some interesting floppy disks that convert to HFE format work perfectly. This format makes the Gotek drive most reliable.

Now to my question. The vintage computer forum at http://www.vcfed.org/forum/archive/index.php/t-44638.html mentioned some interesting manuals. Archive.org has some manuals, Bitsaver does not have manuals about the M6800 development system.
If someone already owns scanned manuals to the following list

M6800 Basic Interpreter Reference Manual
M6800 Macro Assembler reference Manual
M68SFDU Exordisk 11/111 Disk `Drive Unit Maintenance Manual
M6800 Exorciser 11 User's Guide
M6800 Exorciser User's Guide
MEX68PP1 PROM Programmer Module Supplement M6800 Exorciser User's Guide

I would welcome any feedback or questions

--THOMAS


More information about the cctech mailing list