[Coco] reset behavior suggestions?

[Zippster]

Hmm, normally I would go with a regular system reset, but I think I see the dilemma here.
Restating it here to be sure I understand, as the coffee has not quite kicked in yet this morning…   :)


You need to be able to reset the machine (the 6847 really) to possibly change artifact colors
on some games when using a CoCo1/2.  In this case you want to reset the machine and
immediately execute the current cartridge image when the user is pressing reset for that purpose.

You also need to be able to reset the machine, and execute the flash cart menu in the case of
the user being done with that game and wanting to go back to the main menu.

The problem with using a varying length of hold on the reset button is that it uses too much CPLD space.
I guess it could also be non-intuitive for the user.


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.


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).

- Ed




> On Nov 13, 2016, at 12:29 AM, RETRO Innovations <go4retro at go4retro.com> wrote:
> 
> I have one more user interface question for folks, if interested.
> 
> Designs that try to emulate a cartridge seem to need two "reset" options...
> 
> a) a reset that essentially starts the existing game/app/utility over.  One can use this to quickly restart the current app, or reset the game hoping that the right color scheme shows on the screen (http://www.coco3.com/community/2006/01/tech-question-color-artifacts/)
> 
> b) a reset that resets the master system, loading the menu app from disk or ROM again, essentially, start from the beginning.
> 
> My initial idea was that A and B would be distinguished by how long one held the reset button.  short press and release: A.  2s+ reset: B
> 
> But, that requires a "huge" counter in the design, eating up lots of CPLD space. The advantage is only needing to press one button, a button folks are already used to pressing.
> 
> Another is to put a reset button on the cartridge itself. Simple.  The downside is a special purpose button that is only used for reset
> 
> A third option is to put a button on the cart that can be used in conjunction with reset to signify which reset the user wants. This means the button can have other uses, but it then requires 2 things be pressed to denote a secondary reset.
> 
> There may be other options, not sure.
> 
> Thoughts?
> 
> Darren, Zippster, others: what method do you use in your designs?
> 
> Jim
> 
> -- 
> RETRO Innovations, Contemporary Gear for Classic Systems