Program counter range comparator with equality, greater than, less than and non-equal detection modes

摘要

An program counter address comparator includes two comparators comparing an input program counter address with respective reference addresses. The comparators produce a match indication on selectable criteria, such as greater than, less than, equal to, not equal to, less than or equal to, and greater than or equal to, and can be selectively chained. Input multiplexers permit selection of either the program counter address bus or a secondary address bus. The reference addresses and control functions are enabled via central processing unit accessible memory mapped registers.