System and method for comparing values during logic analysis

摘要

Disclosed is a system and method to compare logical values. The system employs a field programmable gate array (FPGA) configured for comparing logical values. The FPGA includes a number of inputs to receive an N-bit sampled value from a target system, where N defines the number of bits in the N-bit sampled value. The FPGA also includes a number of lookup tables configured to receive an M-bit portion of the N-bit sampled value. These lookup tables generate a lookup table output in response to the M-bit portion. Finally, an AND operation is performed on the outputs of the lookup tables that generates an output indicating whether the particular N-bit logical value matches a particular desired value. Note that a single AND gate may be used or a number of AND gates may be used in place of the single AND gate. The tables within the lookup tables are generated based upon a desired logical value and a comparison mask value.