[Coco] Quick 6809 Q for night owls in the US

Steve 6809er at srbsoftware.com
Tue Apr 15 09:37:24 EDT 2014


Can't use the U (or S) register for this loop since the Z-flag is not 
set when doing LEA or LD operations.  These are stack registers and 
should not effect any flags since that would be bad for saving the state 
of the CPU.


On 4/15/2014 6:24 AM, tim at franklinlabs.com wrote:
> I'm not at home to test but wouldn't this work??/
>                  LDU    #1000
> LOOP:    LEAU    -1,U
>                  BNE    LOOP
> All inside the CPU.

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