Xilinx CPLDs: XC9500 vs CoolRunner-II

The two cheapest and most readily available Xilinx CPLD families are the XC9500 and [[Xilinx_CoolRunner-II_CPLD_quick_start|CoolRunner-II]]. Both are in stock at Digikey in a variety of packages. We wondered what exactly the differences are, here's our notes in a table. 

{| class="wikitable" border="1"
|+ XC9500 vs CoolRunner-II
! !!XC9500 !! CoolRunner-II
|-
|Cost||Cheapest (from $1.07 for the 36 macrocell [http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=122-1385-ND XC9536XL])||Cheap (from $1.25 for the 32 macrocell [http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=122-1404-ND XC2C32A])
|-
| Core supply ||[http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=122-1385-ND XC9500XL] is 3.3volt. Older expensive [http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=122-1432-ND XC9500-] is 5volt ||1.8volt core
|-
|IO supply ||XL is 1.2-3.3V IO, - is 1.2V to 5V IO||1.5-3.3volt IO
|-
|5volt tolerant pins||All pins 5volt tolerant||Only expensive XPLA3 portable version
|-
|Voltage translation|| All pins run at the same voltage||2 or more banks with independent supplies
|-
|Power use||Higher power, slightly faster||CMOS technology, lower power
|-
|Goodies||GCK, GTS, GSR||clock divider, clock multiplier, multiple IO banks, GCK, GTS, GSR
|}

Our take away is below.

CoolRunner-II
*Use CoolRunner-II whenever possible
*More modern
*Lower power
*Multiple IO voltage banks

XC9500
*Use XC9500XL if you need 5volt tolerance
*Forget the older XC9500 5volt parts, they're dead
*Might be good for huge quantity projects where a few cents matters

==Special features==
There are also some pins with special features, though they are not used unless specifically enabled in the CPLD synthesis:
*GCK (global clock) - optimized to distribute a clock signal to all macrocells with minimum skew and extra resources
*GSR (global set reset) - optimized path to the Set/Reset signal of all macrocells, allows synchronous reset of the flip-flop in all cells with minimum extra resources
*GTS (global tri-state) - optimized to put all CPLD pins in a high impedance state

==Resources==
*[http://www.xilinx.com/support/documentation/boards_and_kits/ug500.pdf Programmable logic quick start UG500]
*[http://www.xilinx.com/support/documentation/data_sheets/ds054.pdf XC9500XL user guide]
*[http://www.xilinx.com/support/documentation/data_sheets/ds090.pdf CoolRunner-II user guide]
*[http://www.xilinx.com/support/documentation/application_notes/xapp429.pdf 5volt IO with the CoolRunner-II]