pcb-rnd knowledge pool

Abstract: n/a

  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)

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]
)

see also

This feature is used together with the intconn feature for jumper subcircuits not drawn on the schematics (e.g. 0 ohm resistors).