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Re: Source Code for OS?



In article <3A7AC9A8.91EDBD28@usb.com>, Dennis Jenkins  <dennis@usb.com> wrote:
 
 
> And what does that do?  I see the reference to the data in latch on a
> slot 6 floppy drive, but what is at $ADBE?
 
It must be some address in the Applesoft or Integer Basic ROM's.....
 
> I assume it is in the global memory space of DOS 3.3 (ok, all variables
> in DOS 3.3 are globals, but who's counting, right?)
 
This wasn't a variable but an anonymous memory address.  A variable
is a memory address with a symbolic name attached to it, however the
initial "$" means the "ADBE" is to be interpreted as a hexadecimal
number, not a symbolic name.
 
> Why the ADC #1?
 
Wny not?  I thought it looked cute....
 
The code doesn't do anything useful -- I was just making it up to
have some 6502 assembly ro ROT-13....
 
>     LOOP:   LDA $C08E,X
>             BPL LOOP
>             CMP $ADBE
>             BNE LOOP
>             BPL EXIT
>             ADC #1
>     EXIT:   RTS
 
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