pcb-rnd - the [nonetlist] patch
The [nonetlist] patch adds an element flag that makes PCB ignore the marked
element when dealing with netlists. This means connecting a net to a pin of
a nonetlist element will not cause a short. The refdes of a nonetlist
part is drawn with color element-color-nonetlist (ElementColor_nonetlist
in the source; default value #777777, grey).
Uses of the nonetlist feature:
- smd jumper: Combined with the [intconn] patch, this
solves the "0-ohm 1206 jumper" problem: the element should be marked
as nonetlist, with both pins set intconn(1) - this will result in a 2
pad element, pads internally connected, that can be part of any one network
without causing short and passing the DRC.
- mechanical parts that should not show up on the schematics:
- mounting hole elements: single pin holes with silk marking the head of the screw
- chassis (often with mounting holes or keep-out areas)
- logos in footprints (no poly support in footprint - yet?)
- mechanical parts which do not have solderable pins (plastic spacers, extra connector shields)
- "spare connectors", e.g. unused/disconnected DIP sockets, pin grids, or connectors in the corner of the PCB for prototyping (dev-board style)
Preservation: gsch2pcb-rnd leaves nonetlist elements in the PCB.
save/load and compatibility
This patch introduces a new element flag. The following example demonstrates
a 1206 jumper footprint:
Element["nonetlist" "1206 jumper, 0 ohm" "" "1206" 0 0 -3150 -3150 0 100 ""]
Pad[-5905 -1181 -5905 1181 5118 2000 5718 "1" "1" "square,intconn(1)"]
Pad[5905 -1181 5905 1181 5118 2000 5718 "2" "2" "square,intconn(1)"]
ElementLine[-2362 -3740 2362 -3740 800]
ElementLine[-2362 3740 2362 3740 800]
Mainline PCB will load the design ignoring internal connections and nonetlist
flag - this will cause shorts on all connected pins/pads and will break
Mainline PCB doesn't save nonetlist and elements are embedded in the file -
once the design is loaded and saved with mainline PCB, the flag is lost.
After reloading the file in pcb-rnd, the element causes the same shorts
as in mainline PCB.
No plans, the feature is complete.