[Coco] CoCo-SDC card on a Dragon64

[Darren A]

On Tue, Jun 23, 2015 at 2:09 AM, Pere wrote:

> Hi Darren,
>
> so this is the RAM byte that contains the SDC bank in use.
> But we cannot just change its contents. Every time I have done
> it, the system has hanged.
> Probably there are some more things to do ...
>
> I have tried:
> POKE &HFF4B,3: POKE&H71,0: EXEC &HB3B4
> Being the last two, the normally used to invoke a coldstart, but it

hangs anyway too.
>
> I don't know what else should be done to get something like
> RUN @3 on a Dragon with DOSPlusExtended, so without your SDC-DOS
>


If you are running Disk Basic (or DragonDOS) from one of the flash banks
then changing to a different bank would require using a machine language
routine, since doing so removes the Disk Basic code from the address
space.  The machine laguange routine should also mask interrupts since an
IRQ will likely call through to a servce routine in the Disk Basic code.


- Darren