Xilinx Student Edition 2.1i

Rating:
Summary: Good upgrade to Xilinx Student Edition 1.5
Review: The Xilinx Student Edition (XSE) 2.1i package is a special 'academic' version of Xilinx's commercial software tool, Xilinx Foundation Express.

Nearly *ALL* functions/features of the commercial software are available in the student-edition software. The missing features aren't necessary for student labwork (synthesis timing constraint editor, float licesne server, large FPGA device implementation.)

XSE is a design package for Xilinx FPGA/CPLD devices. The software consists of 3 major components : design entry, design implementation, and design verification (simulation.)

Design entry - Schematic editor, this is the standard schematic capture tool. You place graphic symbols (which represent logic functions) on a sheet, and use the mouse to 'connect the I/O pins.' The tool is cumbersome to use, and shows its age. Screen redraws aren't perfect, and as you move objects on screen, the program leaves behind graphic debris. Minimizing/maximizing the window forces the application to refresh the display, but it's still annoying. The state-diagram-editor lets you capture designs using state-transition diagrams. The diagram-editor is a Win32 application (very rarely crashes, long filename support), I say this because other parts of XSE2.1i use legacy Win3.x code (and they suck.) Finally, the HDL editor provides a fancy (colored-keywords) text editor for VHDL/Verilog code entry. The HDL-editor is little more than a fancy Notepad.exe (can't even have more than 1 document open), but it works.

Design implementation - PAR (place and route), these tools convert the logic designs into bitstreams for downloading to Xilinx FPGA/CPLDs. In other words, they convert the 'electronic' design into a 'physical' design, something that runs in the real world. The PAR tools eat a lot of memory. With 128MB RAM, the PAR tool easily handles up to 10k gates (XC4010XL.) But when targeting a 50k Virtex, I experienced a lot of swapping.

Synopsys FPGA-Express (for Verilog/VHDL synthesis) is integrated into the HDL editor. It's also optionally invoked from the project manager (if you pick 'hdl design flow.') Not much to say here, except it runs with no hitches. XSE2.1i now provides a 'demo license' which allows you to run FPGA-Express, no need to register on Xilinx's web. The demo-license doesn't support certain features, like the HDL constraint-editor, but it's not really needed for student use anyway.

The waveform simulator is really really bad, in my opinion. It's slow, it's a Win3.x application, and it's crash prone. Large designs are prone to crash. And sometimes the simulator just refuses to start. For long simulation runs, it's all but unusable. Because it's a Win3.x app, it doesn't seem to multitask in the background (meaning you can go and do something else while a simulation is running...the simulation just pauses!)

Compared to XSE 1.5, XSE2.1 improves these specific areas : 1) newer/faster synthesis engine (Synopsys FPGA Express 3.3) 2) better schematic editor (supports Win9x long filenames, but editor is still not a Win32 application...sigh) 3) overall more stable project manager (but still crashes, still a Win16 application, and can *still* take down NT4 workstation) 4) greater device support, up to "50k gates" (Virtex-50)

Some bad things : 1) still A LOT of 16-bit (Win3.x) code...I can't believe I still see this junk in the year 2000. No wonder the box is missing the "Designed for Windows9x" Microsoft logo, because the software doesn't come close to meeting MS's certification requirements! What's so bad about 16-bit code? Well when it crashes, it can jar-jar even NT4 workstation. It doesn't multitask well (i.e. doesn't seem to run in the background.) The waveform simulator is the worst. The schematic editor and project manager are also 16-bit apps, but don't cause as many problems (because their functions don't tax Win16's limitations.) Critical components like the FPGA-Express, and PAR tool are Win32, thank goodness.

(The commercial Xilinx Foundation Express 2.1i shares the same 16-bit/32-bit hybrid codebase...)

As a final note, the box says XSE2.1i supports up to Virtex-50 devices. Strangely enough, installing the included sofwtare service-packs allows project-sizes up to Virtex/VirtexE-1000 and Spartan2-150 parts. Either someone slipped up, or Xilinx has unlocked FPGA design to the academic world. With Xilinx about to announce completely *free* webtools for Spartan2/Virtex-300E devices, seems like this was the plan all along.

Rating:
Summary: Resources that make XSE even better
Review: The XSE 2.1i is simple to use. The hardest part is installing the software and getting the license. There are several very useful resources for the XSE software, development board and programmable logic designs in general:

* XSE tutorial and technical support available at http://xup.msu.edu/ (Great site for students)

* XSE license required to use the FPGA Express (VHDL & Verilog) To get the 'correct' license make sure you go to http://university.xilinx.com/univ/xsepre.htm

* Software tutorial http://www.support.xilinx.com/support/techsup/tutorials/tutorials21i.htm

* Tutorials and examples http://www.xess.com

* Tutorials and Freeware http://www.digilent.cc/

* Complete 2.1i software manual http://toolbox.xilinx.com/docsan/2_1i/

* Self-supportability tools and Problem Solvers http://www.support.xilinx.com/support/troubleshoot.htm

The on-line resouces make this product much better and easier to use.

Rating:
Summary: WAIT for NEW 4.2i version
Review: XSE 2.1I is great BUT the new 4.2i will blow it out of the water.
4.21 will be available in early summer 2002.