[Coco] How Many OR90s can be utilized?

[RETRO Innovations]

On 11/12/2016 1:13 PM, Zippster wrote:
> Will be doing at least one small run when I’m done building and sending out these mini-MPIs.
I figured.
> Plenty of room in the CPLD. I’ll take a look at adding some features, start off with Orch90 default address with programmable addressing
> (user can set it) as an option perhaps.
That's my main problem.

I'm using an XC95144xl, and with all of the FLASH, EEPROM, etc. 
technology, I am running out of CPLD room.

Currently, I have enough space left to devote a bit in my "CocoFLASH 
config register" to turn the OR90 decoding on or off.

But, I wanted to create a "address mapping" register.  Doing so puts me 
way over on macrocell usage (177 MCs),  So I was hoping that simply 
allowing the user to turn on/off a specific CocoFLASH OR90 capability 
would be enough.  The problem is that doing so means 4 channel writes 
will take 16 additional cycles per write sequence, whereas allowing the 
OR90 registers to move would be the better option (but takes too many MCs).

To ensure that each of my designs can be relocated in the IO space, I 
created a "state machine" on $ff80, which does not conflict with 
anything.  By writing some magic bytes to $ff80, one can reset the 
address range of any of my designs.  I can use the same state machine to 
support the

Any Verilog gurus out there who think they can help shrink the design :-)

Jim