I just started playing with the Cedar logic simulator
Windows binaries here.
http://sourceforge.net/projects/cedarlogic/Src here
https://github.com/amty/cedar-logicOne 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