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#96 Hierarchy revisited
Using V2.70.00 rev248 the hierarchy function does produce a workable netlist.
At this point I would comment that it would be nice to be able to treat it like any other symbol and select it from a library.
No default refdes is shown for a hierarchical symbol when first loaded.
TinyCAD DRC does not find this as an error if there are several symbols with no or the same refdes.
I see this is put in as 'Hx' by default by the automatic generator if run but ignores /overwrites any format string (eg. ABC?) defined by the user.
Exporting it as PADS_PCB format into FreePCB succeeds but leaves the hierarchical symbol connections in the netlist.
(Omitting the parts from the list of footprints)
FreePCB then complains that there are non-existing parts when doing a DRC.
The net names allocated are tied to the hierarchical symbol pin name/net rather than any top level name allocated by the user.
(I've not tried multiple nested hierachical symbols yet)
There is a comment elsewhere about the hierarchical symbol pin numbers being disabled for editing.
This means that all pins must be entered at the same time since the number is used in the netlist and must be unique.
Subsequent pin entries always start at '1'.
In fact if the H_refdes.pins entries were omitted from the netlist the pin numbers would be truly irrelevant.
The refdes's of symbols within a hierarchical symbol must be allocated before it is used in a top level design as the automatic generator does not push down.
(Also DRC does not flag an error if multiple symbols inside a H_symbol have the same refdes)
The resulting refdes exported to the netlist is quite complex and long).
I would like to be able to renumber the final PCB but I don't think there is any way to back-annotate this to the schematic and display it there.
(I can do this with single and multiple sheet designs but not hierarchy by modifying the database (V2.60.01))
I suspect that TinyCAD does not have the necessary cross-reference and live substitution capability at present.
I welcome the success of the hierachy system but I still have some problems with using it live.
I hope this is clear enough and of some help.
Phil
