[Coco] Design Question

[Zippster]

I think I’d have to vote separate.  Just to keep programming for it a little more straight-forward.

- Ed


> On Mar 27, 2017, at 1:01 PM, RETRO Innovations <go4retro at go4retro.com> wrote:
> 
> Not sure if anyone has an opinion, but thought I would ask:
> 
> In most (all?) of my Coco designs, I am putting in FLASH ROM support.  This requires, at a minimum:
> 
> bank register
> 
> a bit or two to handle autostart and program mode.  (Say 2 bits).
> 
> I find that I have two ways to handle this.
> 
> Take, for instance, the CocoNIC cart. I could do two things:
> 
> * Treat the NIC and the FLASH components as separate things. The NIC
>   decodes at one base address, the FLASH at another
> * Treat them as a single unit.  NIC registers follow the FLASH
>   registers, so to speak (or the other way around).
> 
> Advantages of the separated idea:
> 
> * Code can be easily written to handle all of the FLASH portions of
>   each cart, without any regard to what else is on the unit
> * nice way to easily add the support to any cart
> 
> Disadvantages:
> 
> * Takes a bit more logic to handle
> 
> Advantages of combining:
> 
> * a bit less logic (15 macrocells, in general
> 
> Disadvantages in combining:
> 
> * Programming code needs to know more about cart use:
>     o If NIC, programming regs are *here*
>     o else, if arduino interface, reg are *there*
>     o else...
> * Makes it a bit more work to add FLASH to a cart
> 
> Advantages:
> 
> * 15 extra macrocells to use for other things.
> 
> I am leaning towards maintaining the separation, but thought I would canvas for opinions.
> 
> Jim
>