Abstract: A measuring apparatus for measuring the time of execution of instructions or the number of cycles that addresses are within a selected address range of a memory. The measurement includes a measurement of any common subroutines that have been called by the instructions within the selected range. The measuring apparatus includes range circuitry connected to the address bus of the memory that detects instruction addresses within the selected range and instruction addresses within a common range having the common subroutines. The measuring apparatus further includes link logic for controlling a counter to both measure the instructions within the selected range and measure instructions within the common range when they immediately follow the selected range on the address bus. In the preferred embodiment, the memory is organized in ranges so that the first range begins at the first memory location in the memory and the last range ends at the last memory location in the memory.

Abstract: A system for measuring program execution time compares all addresses occurring on a memory bus to an upper limit number and a lower limit number to produce a signal which indicates if each address occurring on the memory bus is within a range represented by the upper limit number and the lower limit number. The signal is utilized to either enable incrementing of a counter at a predetermined rate or to increment the counter once for every new address occurring on the memory bus within the range. The contents of the counter represent either the accumulated time of execution of instructions having addresses within the range or the number of instructions executed having addresses within the range. The system includes a display for displaying the contents of the counter.