Set Track Width Using Custom Rules

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1

I’ve been trying to set track widths depending on class using custom rules, but I’ve found a few issues.

I have setup a netclass ‘P8V0’ which contains the nets ‘P8V0 Supply’ and ‘P8V0 Return’ using the pattern ‘/P8V0*’ and assigned the netclass ‘P8V0’ to them in the schematic editor.

When I use the custom rule below using the netclass name, it doesnt apply:

(rule "P8V0 2"
	(condition "A.NetClass == 'P8V0'")
	(constraint track_width (min 2.5mm)(max 2.5mm)(opt 2.5mm)))

However when I directly call on the net name using the code below it works fine:

(rule "P8V0 1"
	(condition "A.NetName == '/P8V0 Supply'")
	(constraint track_width (min 2.5mm)(max 2.5mm)(opt 2.5mm)))

To make it even more confusing on another PCB I have this rule which works as expected:

(rule "JTAG In2.Cu/In5.Cu"
	(condition "(A.Layer == 'In2.Cu' || A.Layer == 'In5.Cu') && (A.Netclass == 'JTAG')")
	(constraint track_width (min 0.373mm) (opt 0.373mm) (max 0.373mm)))

I’m obviously missing something, but unsure what. I have tried using global labels instead of local labels and no change.

Any ideas? Its probably going to be something obvious.

2

I’m assuming you are using 9.0: use A.hasNetclass('P8V0'). Checking equality won’t work because in 9.0 nets have multiple netclasses and in general will be in the Default netclass also.

3

If I change the rule to:

(rule "P8V0 2"
	(condition "A.hasNetclass('P8V0')")
	(constraint track_width (min 2.5mm)(opt 2.5mm)(max 2.5mm)))

It works.
I think the issue is ‘NetClass’ holds a list of the net classes that the object is a member of, and returns false when checking for a single net name.
Where hasNetClass is a function that returns true if the object NetClass holds the entered name.

NetName threw me off thinking NetClass would be the same, especially as it doesnt throw any errors.

4

I missed your reply, and yes I agree its me thinking NetName and NetClass are used in the same way.