[Coco] Was, Banked switched roms, Now NitrOS9 and the J&R Banker

Bruce Calkins bcalkins at disaster-relief.net
Thu Jan 29 13:10:51 EST 2004


Well, I know that OS-9 L1.0 and L1.1 could be patched for the J & R Banker.
The problem in understanding the patch was that the patch was done on the
working disk.  (DSKO$)  I guess what I'll have to do is to compare the
original kernel modules and the modified kernel files until I find the
changes.  I'm guessing the CRC was up dated too, so that might be my major
clue.  Then I'll need to figure out just what they did and apply that to the
appropriate module in NitrOS9 L1.  Of course I don't really have any idea
what I'm doing, but, I did originally get this machine for a learning tool!
:-)

O.K. I took some time out to work on this.  Here's what I have so far.  J &
R Banker's  OS9BTFIX / BAS program writes the following values to the OS9
Module in hex, 10,8E,F0,00 at offset 26FC-26FF,  20,1D,8C,FF,00,25,31,20,42
at offset 2700-2708,  20,B7 at offset 2749-274A,  and changes the CRC to
D4,F3,DA at offset 2E41-2E43

Now, I don't have a clue as to what this change does.  I've only deciphered
what was changed.  And the core question still is, what will need to be
changed in NitrOS9 L1 to make it work on the J & R Banker?

Can anybody help me here?

Bruce W.


> I have a J & R Banker board in my CoCo I which I haven't turned on in
> years (decades) anyways mine had 512k.  It sure made OS9 Level 1 fly,
> since the first thing it did was iniz the drive (maybe format) then move
> my cmd directory over to it.
>
> ~David Hazelton




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