Abstract: A serial poll request node and circuit are provided. The node includes a data token input and output, first and second acknowledge inputs, and an arbitrating switch. An acknowledge circuit is configured to receive as an input the first and second acknowledge inputs and at least one output of the arbitrating switch, and to generate an enable signal in response to at least the absence of a pending request signal and both the first and second acknowledge inputs simultaneously receiving acknowledge signals.

Abstract: A switch for routing information to one of a first and second outputs, respectively, is provided. The switch includes first and second multi-rail control paths, first and second mutex gates, and first and second demultiplexers. The first and second multi-rail control paths are cross connected into the first and second gates. Outputs of the first and second mutex gates are cross connected into the first and second demultiplexers. First and second data paths input to the first and second demultiplexers, respectively. Data on at least one the first and second data paths is routed to one of the first and second outputs based upon a state of the outputs of the first and second mutex gates.

Abstract: A high impedance acknowledge circuit configured to generate an acknowledge signal is provided. An input circuit is configured to receive an input signal and an enable signal. An output circuit is configured to receive a plurality of intermediate signals from the input circuit, generate an output corresponding to the input signal when the output circuit is in an enabled state, and assume a high impedance state when the output circuit is in a disabled state. An acknowledge circuit is configured to receive as an input at least two of the intermediate signals, and to generate the acknowledge signal based on at least the enable signal.