[Coco] Programming help

Mark McDougall msmcdoug at iinet.net.au
Tue Jun 25 09:25:31 EDT 2013


On 25/06/2013 11:13 PM, Bill wrote:

> I’m trying to write an assembly language routine, and having what’s probably
> a very simple problem.

> 70          ORG   $0EOO
> 80          ORCC #$50
> 90          LDX   #$8000
> 100         LDY   #$FFC0      *BANK 0
> 110   COPY  STB   $FFDE
> 120         LDB   O,Y
> 130         LDA   O,X
> 140         LDB   $08,Y *BANK 00/00
> 150         STB   $FFDF

It's been a long time since I did any 6809 assembler, but at first glance 
this looks like it doesn't do anything useful; switches in roms, reads 3 
bytes, switches out roms, then continues to execute whatever's in memory 
after line 150!?!

What are yo trying to do?

Regards,

-- 
|              Mark McDougall                | "Electrical Engineers do it
|  <http://members.iinet.net.au/~msmcdoug>   |   with less resistance!"



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