Lately I try to ignore it because it seems that the only consensus is that there is no consensus.
Today however I bumped into another thread, this time on gitlab:
And this is where it starts costing time of KiCad developers.
In an attempt to look at what other software does, I did an image search: https://duckduckgo.com/?q=eda+schematic&t=h_&iar=images&iax=images&ia=images
and then started identifying the software that made the images.
I found a total of 26 sources of programs that use simple straight wires for a “no connection” and NONE identifiable programs that used hop-overs to indicate crossing wires are not connected. I did find a handful of images of schematics with the “hop-over” bows, some of those were hand drawn, and most of them seem to be post-processed for publishing purposes, but none of those images had a link or name to software which made them.
All of the EDA programs (and other sources) I found that use straight crossings as “no connection”. The sources I found are:
Apache Design Electric
Elektor (magazine with “house style” for schematics)
KiCad lceda.cn 立创EDA
Without doubt I’ve missed some programs, so if you know of other EDA programs then please add them and add whether they use simple straight crossing lines or “hop-overs” for crossing lines that do not connect. Preferably add a link and a screenshot.
Please try to keep this thread free of personal opinions. (We already have long threads full of those) Just add links to programs or identifiable screenshots, and state what method they use for crossing lines with or without connections.
Every program I have ever seen uses dots to indicate connections.
One thing to note is that while the default for all these programs may be to use straight-line crossovers, it’s possible that they support other crossover styles. Altium Designer, for example, has an option to display crossovers as arcs that is disabled by default. When enabled, it looks like this:
FWIW We never allowed two wires connected at a cross. This is an old requirement that I believe started with the military. The reason is after a few generations of copies (xerox not digital) the difference becomes less than obvious.
Our standard was to always make such connections with an offset so crossed wires are NEVER connected.
I don’t recall any ECAD programs that added a “hop” automatically. My recollection is that hops were always on hand drawn schematics
Not just xerox copies getting garbled over multiple generations, but also the old-style blue photosensitive paper. (Developed with ammonia, those machines and fresh copies smelled awful, yet oddly nostalgic now…)
Given this is a personal preference issue (e.g. my preference is to have hop overs as they are much easier to read and look better), I don’t see any negatives for KiCad supporting such a feature. This could be a setting that can be enabled or disabled and the user can decide how they want it to look.
Now there is of course question of “is this a high priority?” probably not as there are loads more features that would be better to spend time on. However I don’t think this means it should be removed from the wishlist. A motivated contributor could decide to write the code (after discussing implementation details in advance with the lead dev team of course).
I kind of like the hop over style of altium. I feel it makes the design intend a lot clearer. Visio also does it that way. And visio has the issue of needing to support hop over multiple nearby lines in one go which will be unlikely in a pcb design program as buses are shown via a bus tool.
So i would use it if kicad would give me the option to have them.
That aside, i always wonder if photo copy really is still done in any modern office. I mean the one in mine would gather dust if our cleaning staff would not be as diligent. And that even though it is the only scanning and printing option around.
In Altium, the option is per installation and not tied to the design files. This is a good thing as my preference is strongly against hop-overs so I don’t have to look at them when opening other peoples designs. If this feature was to be implemented in KiCad I would suggest doing it the same way.
Hop-overs were used in “ancient” times in water pipe schematics. International standards (like ISO, IEC, IEEE) for water pipes or electrical connections don’t use or allow them except for some very specific situations, and neither do US standards like from ANSI, NEMA, EMSD. I think there are some local or state-wide organizations that use them, though. But I think it’s more a hobbyist thing for people who are not used to read schematics.
Tunnel is what’s used in most standards if it is important to be specific (i.e. which line has to be on top) and to differentiate it from “None” (in above image), like if it cannot happen in the same box/location, etc.
Curious when using tunnel how would you show a connection?
Does your schematic have a note showing the meaning of the line style?
I can see that it looks kind of neat in your above example, however I believe it is a mis-read waiting to happen. As I say this I wonder what folks use the schematic for? (in addition a database for the circuit board)
In the companies I worked for the schematic was an odd drawing. It was not on a parts list (because you couldn’t purchase one). Mfg can built the part/device without it. The only other folks who might need it would be the test engineers.
Only other time it might be needed is if down the road there is an issue with the product and the engineer assigned was not around when the schematic was drawn.
I’ve had to work with many old schematics in my career. From experience one should make them as bulletproof as possible.