[Coco] Laptop Saga, 512K Basic

[jdaggett at gate.net]

On 23 Aug 2012 at 6:10, Kip Koon wrote:

> The XC9500 series is such a big chip.  I can't possibly use all the pins
> in my project. al-williams.com has a little board that can plug one side
> into a breadboard. The other three sides have to be wired manually to the
> breadboard.  I'd like to find some type of quad to dip adapter to use for
> breadboarding purposes. Does anyone know of such an adapter I can use to
> plug all pins of the XC95xx chip directly into my breadboard?


Kip

There is no way that you will find a 84 pin PLCC to 0.6inch wide DIP adaptor that will not cost 
you and arm and a leg. Any of the professional services that would offer such a product 
would be well over $100 if not over $200 per unit. 

If you are trying to do anytime of dyanamic address translation then the XC95108 is more 
CPLD than needed. There are smaller packages. In fact a complete simple VGA section can 
be done in a XC9572. I will have to look around on another hard drive but I have the HDL for 
a GIME compatible MMU that will fit into a XC9536 44 pin CPLD. 

XC9500 series are getting hard to find, the XC9500XL series are still stocked but they too 
soon will go the way of the dodo bird. Ebay and some of th eobsolete part houses will be the 
route to obtain those chips. Digikey still stocks the XC9536XL and the XC9572XL in 44 PLCC 
package. After they clear that inventory they will no longer stock them. The  Coolrunner 2 will 
be the only ones left in stock and their inputs are not 5 volt tolerent. You will need fet bus 
switches on the I/O pins for interfacing to 5 volt logic. Digilent Inc has a CMOD that is a 
Coolrunner2 64 macrocells CPLD (XC2C64) that is on a 40pin dip board. It also has the 
JTAG header pads for programming the chip in system. Cost for that is about $23. I have 
dealt with them in the past and they do make very good products. You will need two to three 
bus fet switches like TI's SN74CB3T3257. For breadboard you will need a SOIC to dip 
adaptor for these parts also. 

No one said breadboarding was cheap!

james