John,

A busripper is just a way of saying that a change happened. The geda bus
ripper symbol is two pins with a graphical line where one pin is a net
type and the other pin is a bus type. Geda doesn't go any further then
that.

In my implementation a bus ripper is two pins and both pins can be bus
pins or one pin can be a net pin. Again it just represents that a change
happened and graphically it could be reduced to a single non-visible
dot. 

The renaming comes into use when you design some reusable symbol for
example an 8 bit by 24 address line memory module. To build a 16 bit 24
address line memory module use two of the eight bit ones. Bring the 16
bit data bus in and then use a bus ripper to split the data bus into two
smaller buses.

At the symbol, rename (renumber?) the buses.

Big bus = data[0-15]

bus1 = data[0-7]

bus2 = data[8-15]

inside each symbol the nets are bus = data[0-7]

up one level one bus is data[0-7] the other is data[8-15].

Steve Meier 

> I"m interested to hear more about the re-netnaming concept.
> 
> With chip design style netnaming, you can use a wires only module to 
> rearrange and change names.  Starting with
> a bus called add-io-data<0:28>, you can plug it into a module that does 
> nothing but rename and has straight through wires, maybe 
> with different groupings.
> Then the outputs have new names.  The top level names in the hierarchy are 
> still going to be part of the netlist, so you could use 
> them as the netnames.  A bus ripper sounds like a wires only module to me.  
> Am I warm?
> 
> John Griessen
> 



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