[Coco] reset behavior suggestions?

RETRO Innovations go4retro at go4retro.com
Sun Nov 13 12:11:33 EST 2016

On 11/13/2016 11:09 AM, RETRO Innovations wrote:
> On 11/13/2016 8:13 AM, Zippster wrote:
>> The first, and simplest option that pops into my head is to execute 
>> the currently selected ROM image on
>> a machine reset, and require a power cycle to go back to the cart 
>> menu (power button).
>> This is probably what I would go with in a situation like this just 
>> to keep it simple and intuitive.
> We considered that, but it's tough to store which cart was active 
> (Coco memory can;t be used, as you can't guarantee a safe spot, and I 
> need to reset the "bank" register in the CPLD to ensure the menu 
> runs.  I don't have a safe place in the CPLD to store the bank register
>> Thinking of Art’s suggestion of holding a key down to select which 
>> type of reset…
>> If you have a way of preserving the start address of the currently 
>> selected ROM image on the board through a
>> reset, you could have a reset execute your main menu code, and from 
>> there check for the key being depressed.
>> If it is, execute the last used ROM image immediately, if not, run 
>> the menu (or vise versa).
> If I knew of a 2 byte location I could guarantee was free, I would.
> Jim
I guess I could just not reset the bank register at all (I think Barry 
suggested that as well), and use power cycle as the hard reset.  I think 
others do that, and I guess I can go there, but in the CBM world, we try 
to avoid power cycling at all costs, since it is conjectured to damage 
the custom ICs, and we're concerned about that.


RETRO Innovations, Contemporary Gear for Classic Systems

More information about the Coco mailing list