Logic Analyser using Spartan 3 FPGA


I came across this gem of a posting one day while shopping around for a logic analyser, I already have a couple, the Intronix LogicPort which is good for CAN/SPI/RS232 but its useless for anything faster, I also have an ancient HP 1650A which is good but bulky and time consuming to setup.

I’ve already got a couple of FPGA based things, and i wanted to expand my knowledge with them.

The project is at Sump , you’ll need something like the Digilent Inc Spartan 3 and the programming tool Adept, oddly Digilent go to the trouble of including a hand cut out piece of paper with a web address to get Adept, but its a 404.

The Spartan board only comes with a parallel port adapter, which is getting rare these days. I just came back from Fry’s Electronics looking for a motherboard with parallel and 9xxx CPU, and only the cheapest one at $89. They had one other PCI adapter but its deceptive, since its actually a PCI to USB to printer port  adapter, so effectively a USB printer port adapter, these are useless for pretty much anything except printers, and even then its a chore.

I opted for the Digilent USB programming cable and the 1000K gate option. However the Digilent cable does not work with ISE, at least not that i could figure out.

As an excellent option the Oak Micros omla32 gives you the ability to add 5V inputs and IDC ribbon style cables, similar to the Agilent offerings, however oddly at the time of writing you can’t use the Agilent cables.

So a few days later the bits all arrive and i start to setup the development environment, Xilinx WebPack ISE, and oh boy this thing goes to new heights in being a PITA to install, so skip what i did and ignore the webinstaller, instead download the large 5G 11.1 installer with something like wget/getright/flashget etc.

Once that is finished, untar the tar file, run the installer, wait forever as its a tonne of tiny little files that even on my WD velociraptor takes ages to install.

Don’t install webtalk because its annoying and wants to upload project feedback via SSL or email seemingly every time you build a project, and I’d suggest not running the update from inside the installer, instead wait til its all finished and run the updates separately, then install the first round of updates (over a 1G of stuff), then run the update again, it’ll want to install a 3rd set, for me this failed on every computer and every OS i tried it on, so i downloaded the .exe files for the WebPack Spartan 6 and installed manually, that fixed it. Normally it got to 10% and failed, it also backs up half the program each time you run the installer, before its verified the downloaded files are ok, no CRC checks, so it takes absolutely forever if you do the retry since it deletes all the tiny little backed up files and redoes it again!

It took me about 8 hours of downloading and installing to finally get it working.

Then i downloaded the Logic Analyser files from Oak Micros, he has an excellent guide to getting all going Downloads this includes an exentensive how-to and the project files.

Because I’d used 11.2 and the 1000K spartan, I spent ages trying to tell ISE to change the device from the standard chip, turns out that its just not worth the bother, recreate the project with the right chip numbers.

XCS31000 and XCF04S

Then you’ll have to change a couple of settings to tell it to generate the right files, i didn’t note (in my moleskine) the correct changes , so I’ll update this post with them later.

Pics Plz!



ISE Settings





Hack A Day had a post on the sump and a derivative.