9825B/T schematics



#4

I need technical infos (schematics, service manuals) about the 9825T. In my machine obviously some build-in ROMs (Strings, Adv.Prog., Ext. I/O) are either defective or can't be addressed. I have to know which IC contains which ROM. The adress logic in the 9825B/T is different from the 9825A. So the schematics for the latter don't help.

Achim


#5

HPCC has reverse-engineered schematics for whichever 9825 has 64K RAM and almost all the ROMs built-in (and also similar schematics for the 9831, including both the 4K and 8K RAM boards that were used in the other 9825 versions).

The only problem is that AFAIK said schematics just show the ROM chips and don't indicate which of the extension ROMs is in each chip. Still, if you think these might be of help, get in touch.


#6

Whom should I contact at HPCC?

Achim


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