A computer contains many integrated circuits that enable it to perform its functions. Each chip incorporates from a few to many thousand logic gates, each an elementary circuit that performs Boolean and, or, exclusive or, or not operations on bits that are represented by electronic states. The CPU is usually the most complex integrated circuit in a PC.
Previous chapters have examined the 80×86 microprocessors’ instructions for moving data, performing arithmetic operations, branching, and utilizing subroutines. The 80×86 and other CPUs can also execute instructions that perform Boolean operations on multiple pairs of bits at one time. This chapter defines the Boolean operations and describes the 80×86 instructions that ...