RE: Formatting routines

From: Baltissen, R (Ruud) (
Date: 2001-11-01 07:38:31

Hallo Rhialto, Spiro,

Thanks for answering. I know how it generally works, just like the story
Rhialto works. Unfortunately I'm a hairsplitter in this case and I need the

> The original IRQ routine calls $F2B0. At $F2E9 it checks $0020. I don't
> where this variable is intialised. Following both possibilities $F2F9 or
> $F99C I have no idea where the JMP instruction at $0600 is executed.
> As you see JOBSZP+x ($00+x) is filled with a code. Where is this code
> examined and acted upon?

The above part describes the part in the code where I stuck. To be exactly:
I stuck at $F2E9. 
After some studying yesterday evening, my intuition says the program resumes
at $F2F9. The subroutine at $F393 transforms $E0 into $60 for the variable
JOB/$45. At $F3F7 JOB is cheked on #$60, true, so it "execute memory"
subroutine at $F36E is called. This routine adds 3 to JOBN/$3F. Remember:

>  STA  JOBSZP+3	; transmit
JOBN contains the value 3 so the result is 6. This ends up executing the
program at $0600. If this is correct, then the main question is:

---  What is the initial value of DRVST / $20 as this seems the key of my
problem ??? ---

For Spiro:
> You can read german, don't you? 

Das solltest du jetzt schon wissen :)

> and send the relevant parts,

Please do, especially those regarding DRVST. Many thanks. 

   / __|__
  / /  |_/     Groetjes, Ruud
  \ \__|_\


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