Path: utzoo!mnetor!uunet!husc6!cfa!ward From: ward@cfa.harvard.EDU (Steve Ward) Newsgroups: comp.lsi Subject: Re: Posting schematics... Message-ID: <920@cfa.cfa.harvard.EDU> Date: 16 Mar 88 17:25:01 GMT References: <915@cfa.cfa.harvard.EDU> <8803112135.AA17866@venera.isi.edu> <3908@cup.portal.com> Organization: Harvard-Smithsonian Ctr. for Astrophysics Lines: 66 Summary: for the masses or the specialists? I may be mistaken, but I thought the original idea was to formulate a simple, inexpensive, universal way to interchange schematics to the great masses awaiting electronic enlightment :-) It does seem to me that there are two ways to go: first, what is admittedly the "right" way, which is to say EDIF. Second, to do something that is readily available and affordable to everyone, including basement amatueurs. EDIF will certainly require lots of programming and the goodwill free dessemination of those programs in order to receive "universal interchange" capability. If there are those out there in netland who are willing to this programming and share it then great, go for it! EDIF is capable of being used to describe the schematic graphically and electrically. Remember, though, that an EDIF-to-plot translator will be needed. The best one would be EDIF-to-HPBL followed by EDIT-to-Postscript, though there HPBL-to-Postscript translator(s) floating around the net, I believe. As I understand it, EDIF allows the definition of graphics symbol to plot mapping to be done by the user. In other words, EDIF does not provide a specific schematic definition methodology such that it defines the graphics plot representation of the schematic. The definition and interpretation of drawing the schematic onto paper or whatever is left to the user. This is really a question, since I am not sure my understanding is correct, and I do hope it is wrong. Someone who really knows should comment on this. If my understanding is correct, then a definition of how to reprsent schematics in EDIF with respect to a coordinate system, scale information, parts (graphics symbols) defiintions (presumably vectors) etc will have to agreed upon. If I am wrong, then EDIF provides a full graphics description capability as well as circuit topology capability and this particular concern is unfounded. In any case, it does leave a lot of software to be generated if the intent is to provide lowly PC (and clones), MAC's, and variouus workstation users to interchange schematics. I suppose the two critical pieces of software would be the EDIF-to-HPGL translator and an EDIF netlist extractor that would generate a generic ASCII wireing list, component parts list, and hopefully an English language ASCII netlis. Come to think of it, I guess a third piece of software is needed: a program to generate or otherwise encode a schematic into the necessary EDIF format. I guess this is the real problem. Who has this capability, and for the masses who do not, how can this capability be easily provided? If there is an easy, simple, universal solution to this last program then please tell us. The second cheap and dirty approach, using a simple netlist and an HPGL file of the schematic has already been discussed. Its merits are that many low-cost PC and MAC programs exist that allow generation of schematics netlist files and HPOBL files, including plotting of HPGL files on dot matrix printers. Also, HPGL dot matrix printer support is simple to implement independently. I certainly favor EDIF if the last problem of how to provide the masses with the means to generate schematic EDIF files can be surmounted. If the idea is really to provide interchange for those using commercial CAE/CAD workstation systems, then NEVER MIND! fMy lowly PC at home and our overpriced CAE system at work can generate netlistss and HPGL files and plot them , but neither know zip from shinola about EDIF. o