digraph {
        {rank=same; title S0A S0B}
        title [label="Nameplate\nLister" style="dotted"]

        S0A [label="S0A:\nnot wanting\nunconnected"]
        S0B [label="S0B:\nnot wanting\nconnected" color="orange"]

        S0A -> S0B [label="connected"]
        S0B -> S0A [label="lost"]

        S0A -> S1A [label="refresh"]
        S0B -> P_tx [label="refresh" color="orange" fontcolor="orange"]

        S0A -> P_tx [style="invis"]

        {rank=same; S1A P_tx S1B P_notify}

        S1A [label="S1A:\nwant list\nunconnected"]
        S1B [label="S1B:\nwant list\nconnected" color="orange"]

        S1A -> P_tx [label="connected"]
        P_tx [shape="box" label="C.tx_list()" color="orange"]
        P_tx -> S1B [color="orange"]
        S1B -> S1A [label="lost"]

        S1A -> foo [label="refresh"]
        foo [label="" style="dashed"]
        foo -> S1A

        S1B -> foo2 [label="refresh"]
        foo2 [label="" style="dashed"]
        foo2 -> P_tx

        S0B -> P_notify [label="rx"]
        S1B -> P_notify [label="rx" color="orange" fontcolor="orange"]
        P_notify [shape="box" label="W.got_nameplates()"]
        P_notify -> S0B

        {rank=same; foo foo2 legend}
        legend [shape="box" style="dotted"
                label="refresh: NL.refresh_nameplates()\nrx: NL.got_nameplates()"]
}