gEDA-user: Re: hierarchy of schematics

[John Griessen]

Kai-Martin Knaak wrote:
  My guess is that all net names are
>> global, and in-1.sym and out-1.sym (for example) are purely  
>> informational.  I also don't know if the DRC is smart enough to tell  
>> you if an output on sheet A is connected to an output on sheet B.
> 
> Just tested this the other day for a set trivial sub sheets. 
> Result: Pin names and components receive the refdes of the top level
> symbol as a prefix. Thus they are strictly local to the sub sheet. It is
> even possible to source the same sub sheet several times in the master
> sheet. 
> The port symbols in-1.sym and out-1.sym are not quite informal. The
> important part is their refdes. The netlister gsch2pcb checks for every
> pin label of the top level symbol if there is a refdes with the same name.
> The drc2 output will issue a warning, if there is a pin in the top level
> symbol that corresponds to no port on the sub sheet. It will also warn if
> a port symbol does not connect to a pin in the top level symbol. 
> 
And also put a source=some-schematic-name.sch  attribute on the symbol
that represents the subschematic.
> 
>> Some mechanism to automatically generate a "sheet symbol" would be very  
>> useful.
> 
> Ack. This is, what John G. was talking about. 
> 
> ---<(kaimartin)>---
> (I will netlist my first big sub sheet project today after the unconnected
> pin errors have been dealt with...)

Andy Peters wrote:
 >> We need to dream one up, a gschem schematic to sub-schematic-symbol
 >> genreating script, that is....
 >
 > Agreed, this is necessary for board designs (I won't do an FPGA design
 > in a schematic).  It's impossible to get even a small design to fit onto
 > one B-size sheet, considering how things are scaled in gschem.  (My
 > little IR volume control design is three sub-sheets plus a top level.)

There is a script you might like on 
http://www.gedasymbols.org/user/john_griessen/  jgboxsym  It's like djboxsym to 
launch, but makes more compact symbols so I can cram more into a B-size sheet.
I do that and use an actual B size (11 x 17 inch) paper tray to print them.

John Griessen
ex chiphead