[Coco] Bug in VCC ???

[William Astle]

On 14-04-16 11:46 AM, Luis Antoniosi (CoCoDemus) wrote:
> I found VCC does Half-Carry different from 6809.
>
> doing this:
>
> ldd #$0fc9
> addb #$40
> adca #$00
>
> it will set the HC on VCC but not on 6809.
>

I would have expected the 6809 to actually set H in this case. The 
references I have available say it should. After all, you do have a 
carry from bit 3 to bit 4 during the ADCA.

Still, the H flag is only used by DAA. I would be surprised if it is the 
problem in this case (unless the code that's failing is using DAA somehow?)