[geda-user] Is someone using busses in gschem?

[Stefan Salewski]

I just added arc editing support to PetEd.rb, so I may call it "feature
complete" with the exception to pictures and busses. I guess pictures
are mostly useful for redesign of existing schematics, so I may add it
later, it may be some work.

For busses -- I was not able to really made use of it when I started
with gschem many years ago, so I never used it, and still have no idea.

So I intend to drop bus support for now, and maybe add it much, much
later. But of course, when people really use busses and find them
usefull, then I have to learn how it works and add it soon.

[gedau-1XeMD6fE9sqV9CSZFf/]

I do, sometimes.

Post by Stefan Salewski
usefull, then I have to learn how it works and add it soon.

Purely graphical, connections are due to netnames. First I found this
strange, but when I started to use it I started to like it. Checking
whether all nets connected to a bus has a name is a good idea, tho.

HTH,

Tibor

[Bert Timmerman]

Post by Stefan Salewski
I just added arc editing support to PetEd.rb, so I may call it "feature
complete" with the exception to pictures and busses. I guess pictures
are mostly useful for redesign of existing schematics, so I may add it
later, it may be some work.
For busses -- I was not able to really made use of it when I started
with gschem many years ago, so I never used it, and still have no idea.
So I intend to drop bus support for now, and maybe add it much, much
later. But of course, when people really use busses and find them
usefull, then I have to learn how it works and add it soon.

Hi Stefan,

Graphical usage only.

I still haven't figured out wether the bus rippers actually add
functionality to the schematic, as to be able to do functional ERC on them.

Kind regards,

Bert Timmerman.

[DJ Delorie]

I have an example of using busses here:

http://www.delorie.com/electronics/rx/os-board.html

Page 3 of the pdf or os-bus.sch in the design files.

[DJ Delorie]

So current gschem busses are only a visual guide of connectivity,
with no impact to netlist.

Right. Busses have nothing to do with netlists.

[Alexis Phoenix]

I've used busses which do affect the netlist, in another program and
they're really useful. When I go back to gschem (now I undersand cad more!)
netlist busses would certainly be appreciated here. In the other program
(DesignSpark) you just connect your nets to/from the bus wherever you like,
it by default labels them with the net-names, and they are processed as
individual nets.

Post by DJ Delorie

So current gschem busses are only a visual guide of connectivity,
with no impact to netlist.

Right. Busses have nothing to do with netlists.

[Joshua Lansford]

Post by DJ Delorie

So current gschem busses are only a visual guide of connectivity,
with no impact to netlist.

Right. Busses have nothing to do with netlists.

I use busses. They don't effect the netlist, but they do effect a custom
drc:
This drc verifies that no nets connect together without a graphical element
indicating such.
The script also updates off page connectors to indicate which page(s) they
connect to for nets and busses.
This makes it so that if it doesn't look like two nets are connected, they
aren't. Accidental connections are impossible. (in theory :-P)
http://public.laserlinc.com/Joshua/crossRefSignals.py

[Stefan Salewski]

Post by DJ Delorie
http://www.delorie.com/electronics/rx/os-board.html
Page 3 of the pdf or os-bus.sch in the design files.

Interesting. So current gschem busses are only a visual guide of
connectivity, with no impact to netlist. (Netlist connectivity is
determined by netnames in your example). And the behaviour seems to be,
that 'bus rippers' are generated, when we connect nets to these busses.

Coding that should be not difficult, so maybe I will add it to PetEd
soon. But I am not fully convinced that editing busses is really easier
than drawing some plain lines, at least I did not managed to draw busses
when I used gschem for the first time.

http://wiki.geda-project.org/geda:gschem_ug:pins_nets_buses