I just started playing with the Cedar logic simulator

Windows binaries here.
http://sourceforge.net/projects/cedarlogic/

Src here
https://github.com/amty/cedar-logic

One of it's built in "chips" is .... Z80 ...(heh sorry), which I've been trying to get going in a "circuit".

I read in the "Breaking 6502 apart" thread a post from org who wrote :
Sadly its impossible to simulate full 6502 in Logisim, since it doesn't support bidirectional wires and I have no clue how to implement bus-to-bus connections there.

I'm not sure whether Cedar supports "bidirectional wires". It seems to, as the Z80 load /stores are working. But I haven't built anything yet from the primitive gates / etc to verify that.

Mike