Application specific modules in a programmable logic device

Abstract

A structure and a method provide a programmable logic device including a number of generic logic blocks and one or more application-specific block. Such application-specific block implements a specific function, such as a register file or a memory array. In one embodiment, the application specific block is programmable to be either one or more single-port memory array, a first-in-first-out (FIFO) memory, or a dual port memory array. In another embodiment, the application-specific block can be configured to be a register file, a number of counters, a number of timers, or a shift register. The application-specific block can be used in conjunction with programmable logic arrays for multiplexing input and output signals into and out of the application-specific block. Interconnectivity between the generic logic blocks and the application-specific blocks using a global routing resource integrates into a programmable logic device functions otherwise difficult to implement using only generic logic blocks.