21 Feb
2007
21 Feb
'07
5:51 a.m.
Continuing my story of trying to recover the contents
of the hard drive
in my Horizon 8/16 system, I took Dave Dunfield's advice and wrote a
small program to read each sector from the hard drive and dump it. 30
MB of disk data at 9600 baud, printed as ASCII hex. It took a while.
The mystery remains -- what is it?
There is no plain-text to be found anywhere ... not even accidental
sequences. I thought that perhaps it is a lot of binary data. Some of
it must be code. Searching the hex for "CD0500" (which is "CALL
0005",
the CP/M call vector) has no hits.
I agree with Chuck ... this is probably as test pattern.
I converted your HEX section to binary, and ran it through about a dozen
disassemblers for various CPUs of the era, and found nothing that looked
like code.
Tried complimenting, reversing bit positions, and still nothing that looks
like code - tried droppng the high bit on all of these and didn't see any
recognizable text either.
Perhaps the former owned did a read/write hard drive test before
dcomissioning he system to remove his data from it? (or did a read/write
test when installing it, and never did get around to using it).
Dave
PS: Thanks for the N* TurboDos images, I've just put them up on the site,
along with several other N* images that I have had pending.
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
http://www.classiccmp.org/dunfield/index.html