Programmable logic array integrated circuit devices

Abstract

A programmable logic array integrated circuit device includes a plurality of regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns. Interconnection conductors are associated with each row and column. The interconnection conductors associated with each row include some that extend continuously along the entire length of the row and some that extend continuously along only the left or right half of the row. To increase the flexibility with which the logic regions can be connected to the row and column conductors, adjacent regions are paired and circuitry is provided for allowing the outputs of each pair to be swapped for driving the row and column conductors. Registers in logic regions can still be used for other purposes when not being used to register the main combinatorial outputs of the logic regions. Many other enhanced features are also provided.

The invention claimed is:  
     
         1 . A programmable logic device, comprising: 
 a plurality of programmable logic modules, wherein each programmable logic module includes means for programmably performing a logic function;    a plurality of programmable logic regions arranged in rows and columns of an array, wherein each programmable logic region contains a subplurality of the programmable logic modules; and    programmable interconnect means for programmably selectively conveying signals amongst different subpluralities of programmable logic regions.