Apparatus for programmable signal switching

Abstract

A field programmable interconnect device (FPID) selectively routes signals between signal ports in response to commands from a host controller. Each command includes an address and data. The FPID includes an array of switch cells, each interconnecting a separate pair of the ports and each having first and second control signal inputs. When the first and second control signals are both asserted, the switch cell provides a signal path between the pair of the ports it interconnects. The FPID includes first and second sets of memory cells for storing data. Each first memory cell corresponds to a separate one of the switch cells and selectively asserts or deasserts the first control signal input to the corresponding switch cell according to its stored data. Each second memory cell corresponds to a separate group of switch cells and selectively asserts or deasserts the second control signal input to each switch cell of the corresponding group according to its stored data. The FPID further includes a memory controller for receiving each command from the host controller and for writing data included in the command into each memory cell of a particular subset of the first and second memory cells upon receipt of the command. The address included in the command indicates the particular subset into which the controller is to write the data. The number of memory cells included in the particular subset is a variable function of the address.