The two cheapest and most readily available Xilinx CPLD families are the XC9500 and CoolRunner-II. Both are in stock at DigiKey in a variety of packages, with simple devices starting at around $1. We wondered what exactly the differences are, here’s our notes in a table. More on the wiki.
For a start I’d go with 5V compatible device. I’m total noob with CPLD or FPGA so I will probably try the announced breakout if there are tools for Linux :)
I personally don’t care much about 5V compatible/tolerant. Most uC are 3v3 nowadays so it isn’t a big issue IMO.
AFAIK most use tools on windows. However there was a post about compiling CPLD in the cloud: http://dangerousprototypes.com/2011/01/15/plunify-programmable-logic-design-simplified/
They are but I still do most stuff at 5V, the good old TTL voltage :) I guess it depends what would I do with it, I have no idea (yet).
I’m glad to see you selecting among two of my favorite CPLD families!
I was involved with the development of both families at Xilinx, a while back.
I find the PLUNIFY project to be pretty cool. Back in the 1996 timeframe, we recognized the issues of having to get the design software, load it, etc. A young engineer in my group back then (Josh Silver) developed a product called the “WebFitter” which was (as I understood it) some Java scripts that would give you a GUI, whereby you simply uploaded your source file,
and selected a few fitting options, followed by your part choice, then push
the “compile” button and step back. Your bitstream file could then be downloaded direct from the web. I think we de-commissioned it a couple of years back. Good to see others like the idea!
@jnd, if you need a ekl-cheapo CPLD that is 5V tolerant to hook up to your MCU’s UART port, here is one to consider;
http://www.latticesemi.com/products/cpld/ispmach4000ze/index.cfm?source=topnav
I got pricing of $2.85 from my local distro(Seattle area). Pl check with your distro for pricing. And these are available in hobbyist friendly 48 Pin TQFP package.
cheers,
Ananth
1) can you open a thread in the forum for CPLD discussion it could be fun :-)
2) i’ll be really interesting by a big CPLD 5V tolerant, a kindof army knife, for prototype stuff.
i allready used xc95xx few years ago, software was free but u had to get a jtag cable, now with the busblaster it could more fun !
:-)
I started a new sub-forum for now. I posted all the existing CPLD resources in a first post:
http://dangerousprototypes.com/forum/index.php?topic=1680.0
We have two CPLD breakout boards in progress. They are bread-board friendly, but are intended as simple logic replacement and use the smaller, cheaper 72-76 macrocell CPLDs (not the big 256+ macrocell ones). One is for the CoolRunner-II, the other is for the XC9500XL.