[Coco] Trying to understand Cart Usage on Coco3

[Robert Gault]

RETRO Innovations wrote:
> I am working on a small project that puts some EPROM in the cart port. I am
> trying to test that the EPROM is in the right place, but I don't know how to
> test via the Coco3 BASIC that the EPROM is there.  I've disconnected the CART
> pin from Q on a std Typing Tutor Cart to so some testing, but I am not sure
> where the addresses should be.
>
> Any help would be appreciated.
>
> Jim
>

Is the Cart plugged into the Coco3 cart port or an MPI?

All Tandy Cart/Paks will have their ROMs addressed at $C000; same as the Disk 
ROM. Your device will now not auto-start and you should be seeing the Extended 
Basic message at turn on.
To access the EPROM, assuming there is a program which starts at $0000 in the 
EPROM, just enter EXEC&HC000. Alternatively, you may be able to get the EPROM to 
auto-start without using the CART line by having the bytes in the EPROM at $0-1 
= DK with the program start located at $0002.

Robert