1. A swappable network cell comprising: first and second input ports; first and second networks coupled between said first and second input ports, each of said first and second networks including a first terminal and a second terminal wherein said second terminal of said first network is coupled to said first terminal of said second network; and switching means, responsive to a first state of a digital input signal, for coupling said first terminal of said first network to said first input port and said second terminal of said second network to said second input port, said switching means further being responsive to a second state of said digital input signal for coupling said first terminal of said first network to said second input port and said second terminal of said second network to said first input port.