On Jan 1, 2011, at 1:24 PM, Johnny Rosenberg wrote: > Den 2011-01-01 18:42:49 skrev kai-martin knaak <k...@familieknaak.de>: > >> Johnny Rosenberg wrote: >> >>> here's a >>> new try, which I tested several times: >>> >>> http://ubuntuone.com/p/W8l/ >> >> I just looked at 7400-IEC-1.sym. Some comments: >> >> * some lines of invisible text is not on 100 grid. > > I took a look myself and you're right. I didn't make those though, since I > just modified an existing gate, so I guess they are not on ”100 grid” in the > original symbol files either, but I didn't check that yet. > I didn't add or modify any invisible text except those very unnecessary (?) > author- and license lines. I guess I should remove them entirely.
You should have them if you intend to publish on gedasymbols. > >> >> * the footprint attribute is invisible > > Didn't change that either. Why would you like them visible? Matter of style. Kai-Martin has his, others have theirs. I prefer the footprint invisible so it doesn't clutter the schematic. If I want to know the footprint, I look in the BOM. >> >> * pin labels are invisible Another matter of style, when the symbol itself is sufficient to deduce function. >> >> * if pin labels were visible, they'd collide with the box But they are invisible. >> >> * pin length is 200 units. IMHO, these lengthy pins result in >> awkward artwork, when there is little space on the canvas. This >> is of course a matter of taste. > > 200? Strange. Strange. Looks like 300 to me, except the output pin, which > indeed is 200. I didn't change that from the original symbol either, though. > Actually, the only thing I changed was the shape of the box, and I added an & > sign inside… Another matter of style. Do it how it looks good to you: they are your symbols. > >> >> * the slot attribute is invisible. I like to make it visible, so >> it is explicitly shown on the schematic and can be edited on mouse >> click. I personally prefer it invisible. Do as you please. >> >> * there is no value attribute --> this attribute is used in the bill of >> materials There's no common convention here. I often use the device attribute for this purpose. Then value is for things like resistors. Whatever makes sense to you. >> >> * the visible string 7400 is simple text. That way, it cannot be edited >> in the schematic. In a real circuit it should read 74HC00 or whatever >> flavor of TTL logic should be used. That's an old convention. Due to Ales? I usually agree with Kai-Martin on this matter of style (but on some days ...). Use device= or value= to identify the component if you like. >> >> * the supply nets are implicitly given with the net attribute. IMHO, >> this approach hides information that should be visible in the >> schematic. I prefer to put the power pins in a dedicated 74er >> power symbol. Another matter of style, where I again generally agree with Kai-Martin. I even use the power symbols he posted on gedasymbols. But do what makes sense for *your* flow. >> >> * suggestion: If the symbol complies to a specific IEC norm. How about >> a comment, that refers to the specific norm? Good idea. >> >> * what is the intended use of the attribute device=7400 ? Another style is to use device= as a generic identifier (7400), and put the complete part number in value=, e.g. value=SN74HC00D or some such. > > Don't know, I didn't add that, so it is probably the same as the original > symbol. > >> >> ---<)kaimartin(>--- > > If it's not too much work, could you modify the 7400 symbol to your likings > and then send it back so I can modify the other symbols accordingly? Your symbols should fit your prejudices and intended use. John Doty Noqsi Aerospace, Ltd. http://www.noqsi.com/ j...@noqsi.com _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user