Flex Disc options for the HP 9825

Paul Berger phb.hfx at gmail.com
Tue Jul 19 13:22:20 CDT 2016

On 2016-07-19 2:25 PM, tony duell wrote:
>> There was only ever support for 8" diskette drives, and to support 9895
>> you need the second version of the Diskette ROM which appears to be very
>> rare.  I t sure would be nice if someone who has one of these ROMs would
>> dump the contents or loan it to someone who could dump it, so that we
>> might be able to clone the ROM module.
> It's not totally trivial. The later version module is so large that part of the
> ROM is bank-switched. So you would have to make sure you copied the
> entire ROM and the copied the bank-switching circuitry in the cloned
> module.
> -tony
Yes I saw your schematic, it does not seem too big of a challenge, but 
on the other hand it may be bank switched just because it supports both 
diskette drives and both halve may not be required to support only 9895, 
but without a dump that is only speculation.


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