fiesta@cbnewsi.ATT.COM (eric.c.beck) (06/23/89)
The adverts for Intusoft's $95 spice have also caught my eye. If I remember correctly, though, the number of simulated nodes in the PC version is severely limited. All but the simplest neural networks you'd want to play with would exceed the node limit of the simulator. Also, the level of simulation provided by SPICE is far more detailed than what is required for interesting neural net simulation. Why waste all those CPU cycles on KCL and KVL? Pick a compiler and do it in software on your PC. I wrote a C program about 4 years ago based on a Hopfield net. It could be taught names which could then be retrieved inspite of mispellings, juxtapositioned letters, etc. As I recall the program was not that long - say a hundred lines or so of Microsoft C, most of it input and output formating. Concerning Intusoft SPICE - anybody use it? Does it come with a library (off the shelf transistors, fets, etc), or must one write their own models? Eric Beck homxb!fiesta AT&T Bell Labs Holmdel, NJ
bobc@hplsla.HP.COM (Bob Cutler) (06/27/89)
Several years ago I bought a copy if IS-Spice. From what I could tell, the software was a slightly modified version of the original Berkely code (Fortran version). Some features of the original code were missing, presumably to make things fit into 640K, but nothing drastic. Performance was reasonable, and in most cases, numeric results matched those obtained from a workstation version of SPICE. The software required a math coprocessor and did not come with a parts library. What you don't get for $95 is graphical output (unless you consider line printer plots graphical). At the time, Intusoft sold a package called SOFT_SCOPE ($175) which post processed any Spice 2G.6 output file. It worked OK, but only with a CGA monitor. I found it difficult to use. Berkeley has re-written Spice II in 'C' and called it SPICE III. I thought they were also working on a PC-Version. Perhaps someone in net-land can fill us in on the project. Of course these are my own opinions, and not those of my employer. Bob Cutler Hewlett-Packard Lake Stevens Instrument Division
mmm@cup.portal.com (Mark Robert Thorson) (07/23/89)
I just saw an ad from Intusoft for a $95 SPICE circuit modelling program for IBM PC's and clones. Does anybody out there have experience with this program? Can anyone recommend/disrecommend other SPICE programs for personal computers (any kind of cheap personal computer, like IBM, Mac, or Amiga)? The same ad also offers a SPICE for 386 machines which they claim is the fastest PC SPICE. Cost is $386. (Hopefully they won't raise the price when 486 machines become available.) They also offer a schematic editor for $295 which generates SPICE netlists. These prices sound real attractive to me. Are they too good to be true? Please share your experiences with SPICE on personal computers. BTW, my application is not IC design. I am interested in playing around with neural networks, and I think a SPICE environment would be much easier for trying out different models than, say, a C programming environment. Is this a crazy idea, or what? Are you aware of a neural modelling environment that would allow a wide variety of analog models to be implemented more easily than a SPICE environment?