CPLDs & Xilinx

One of the problems with GALs is the development tools which are way out of date. Though preparing the files by hand doesn't seem to be too difficult. The other problem is the relatively small number of pins.

The next step up is Complex Programmable Logic Devices; CPLDs come in a far larger variety and there or some development kits available for the older legacy designs. 

 

Some of Microchips' offerings, such as the ATF1504AS, can be programmed using WinCUPL like GALS. They also offer a full system such as ATF15XX-DK3-U that can be bought from the likes of Mouser at reasonable prices, though it is quite a high value for reasonable. Lattice & Intel also do similar things.

 

Having done a bit of research and found that Xilinx has released their old Integrated Synthesis Environment; ISE system, which does schematic capture. I decided to check out that route. Schematic capture is not used that much, but, I find it very useful when translating the logic designed in KiCAD and creating other glue logic.

 

I downloaded ISE and played with it first on both a fresh Ubuntu 22.04 and Windows 10 & 11. The Linux system starts quicker. The Windows system did work out of the box for 10 but needed some tinkering for 11, it seems happier being started from the Oracle VM VirtualBox manager. The windows version are the Linux version installed in an Oracle VM Box, so you'll need a system up to running them.

 

 

There is a pdf by Krista Hill snappily entitled Tutorials for ISE/WebPACK Version 14.7 Schematic Capture that guides you through the process.

 

In addition to the software, you will need some hardware to program the chips. In the end, I went cheap and Chinese again, for something which claims to be a XILINX device. This time from AliExpress.

 

Things like the USB Blaster and ST-Link, can be used via OpenOCD but, it was all a bit too much work so I went the easy route. Doing it via OpenOCD means using ISE for the design and exporting a file to download to the chip in a separate app.

The Xilinx bits I've decided to use for the first go are the XC9536 series of chips because they are cheap and come in both a 3.3 and 5v version. The test board is coming from eBay. Inevitably it is Chinese.

The chips I intend to use are also from AliExpress. Initially, I'll use PLCC so I can pop them out and reprogram them, so I expect I'll have to design a board for that.

The various bits of hardware are on their way, so I'll have to get back to more immediate ACE stuff for the moment.