a2retro wrote:

> was the bug in the z80 code or the 6502 code? It would be interesting to 
>  know if my PRORDSK package has the same problem.

It's a bit unclear.  Signs are pointing to the DPB and DPH being incorrectly 
formed for support of drivers >= 256k.  Progress has been bounded by, in no 
particular order:

- Real Life Intruding
- My having forgotten everything I ever knew about Z80 and 6502 assembler
- Ditto for CP/M internals
- An inability to figure out how I was once able to build the PCPI O/S
   image from scratch.

In one small victory, I was able to successfully assemble and link a device 
driver :-).  I am closing in on having a build environment, though, and 
suspect it's something dirt-stupid that I'm doing/not doing.

What is PRORDSK, btw?
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