On Thursday 17 May 2007, Svenn Are Bjerkem wrote: > I have just googled around for a vhdl-ams simulator, and I > only find very expencive ones. Is it really no F/OSS vhdl-ams > simulator out there? > > I know Al is working on Verilog-AMS in gnucap, but is that > the only F/OSS Verilog-AMS initiative out there?
The difference is in the parser. Both have essentially the same underlying algorithms. Where you find one, eventually you will find the other. There was a start from University of Cincinnati a few years ago. As far as I know, it was only a start, and has not been developed past the initial proof of concept. According to its creator, the performance was very slow, and it was a subset. That is the only one I know of. If you want to help with gnucap, you can make it happen. What the simulator takes directly will be determined by a plug-in. I am doing Verilog first because I see a higher demand for it, and because it is less verbose and so is a more reasonable replacement for the Spice format with manually generated netlists. When the language plug-in mechanism is working, which will be soon, it is reasonable to do plug-ins for other languages. After doing the first one, I expect others such as VHDL to be easy. What the simulator takes directly will always be a subset. A more complete version of any language will use the model compiler. Here too, I am doing Verilog first (actually second) because I see a higher demand, and it should be relatively simple to change the front-end to accept other languages that are similar in concept, such as VHDL. The model compiler generates C++, which is then compiled into a model plug-in, that can be attached when needed. Most of this part is already working. I see needs for the following other formats: VHDL Spectre MAST Touchstone PCB (without crosstalk) gschem QUCS HSPICE PSPICE ... There are some others that need more than simple translation: IBIS (90% done) more detail from PCB (with crosstalk) ... The simulator core is not locked into any language. All will use plug-ins. All that exist will be equal in the sense of using a similar plug-in, that stores in the same data structures. Does anyone want to help??? What is needed is to make the plug-ins and compiler front-ends for the other languages. After the first one is solid, you can use it as a model to make others. I see big opportunities here, but I can't do it alone. al. _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user