Hi everyone. I'm new to this list, and a very occasional gschem/pcb user. I make probably one or two small boards per year, single layer. Most of the time using through-hole components because that's what available at my local shop. My question may sound silly or may even have been asked countless times: Are there any official guidelines for naming/numbering pins and pads on symbols and footprints ? Some packages have an obvious numbering like DIP, but what about capacitors, diodes, transistors, etc. ? It could be due to my distribution (Debian), but I always get lost in the symbols and footprints libraries that come with gEDA. Finding the right footprint with correct pin numbering has always been a challenge. For instance, there are 3 different LED symbols. One in "Basic devices", two in "Diodes (generic)". Two of them have the anode on pin 1, the third one has it on pin 2. When trying to find a footprint for it, there are more than five for each of 3mm and 5mm LEDs. For *none* of them does the silkscreen indicate the position of the anode or cathode. LED3 and LED5 from pcblib/~geda actually present this information in their name/description: "(pin 1 is +, 2 is-)". In pcblib/~optical, however, the squared pin is named "-" (in red in preview, still not on the silkscreen). How do you usually handle this ? Maybe you are able to remember what footprint will match which symbol, but I don't use gEDA often enough for that. Or do you build your libraries of symbols and footprints that you *know* (or hope) are correct ? Perhaps the state of the SMDs footprints is not that bad ? I'm now slowly building my own libraries of footprints and heavy-wheight symbols, to avoid mismatch between symbols and footprints. Another reason I'm doing it is because I drill the holes by hand whithout any drill-stand: my footprints have large (60 or 80 mil) pins that allow for some imprecision, with 15 mil drill hole to have the drill bit position itself right on spot, thanks to the copper thickness :) The drawback is that those footprints are obviously unusable if I ever need to have a board manufactured. Thanks for your answers. -- Amand Tihon 13C Rue Arsène Matton, 1325 Dion-Valmont, Belgium +32 479 207 743
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