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Corcomp 9900 Mini Expansion System


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There is a new DSR available for the Corcomp 9900 Mini Expansion System.


Owners of the device have suffered from the same problem as those with the Corcomp Disk Controller DSR before the Millers Graphics eproms were created. The original Corcomp code takes control of the powerup sequence of the TI and provides it's own menu. Unfortunately this menu creates incompatibilities with a number of TI devices and programs.The Millers Graphics eproms for the Corcomp Disk Controller removed the menu and associated code, fixing this incompatibility for the card. The Mini Expansion System DSR code recently became available and a quick disassembly showed a simple fix to remove the Menu. There is only a 10 byte difference in the code, NOPs were used to replace the part in the code that branched to the hostile takeover by the menu code. The code was tested on real hardware at the Chicago Faire, and normal operation of the TI menu is restored, along with proper operation of the Corcomp hardware.


The fixed Eprom code is attached below. Atrax has possession of the code and has agreed to supply Eproms for those that are interested.





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Thank you, Gazoo! And it was wonderful being able to talk to you at the Faire, although you escaped with the Pub Crawl crew before I could get a chance to say goodbye. . . ;) Have much fun with the computer toys I gave you to play with. :)


It was nice to actually meet you, too, Ksarul. I will certainly enjoy those goodies. :)


Sorry for missing your goodbye, but I was trying to stay well in front of Hal's electric cattle prod! The Pub Crawl was pretty entertaining, the only problem being that there were 7 of us still standing when all the bars closed. ;)



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