JPS6454547A - Information processor with program trace function - Google Patents

Abstract

PURPOSE:To execute the program trace without decreasing remarkably a processing speed of a CPU by a buffer memory of a small capacity, by providing a tracer consisting of a buffer monitoring circuit, a buffer memory, and a trace memory. CONSTITUTION:When the execution of a microprogram is started, a tracer 3 starts simultaneously its operation, and a buffer memory 5 inputs an address and a data which are brought to access to a main memory 2 through a bus 100 by a CPU 1. Subsequently, they are outputted to a trace memory 6, but in case when the stagnation of the data of the memory 5 has exceeded a prescribed quantity, a buffer monitoring circuit 7 detects it, and outputs a microprogram inhibit signal 101. As a result, an AND circuit 10 inhibits an output of a ready signal 104 to the CPU 1, and the CPU 1 stops executing the program. Subsequently, when the stagnation of the data of the memory 5 decreases from the prescribed value, the circuit 7 stops outputting the signal 101, and the CPU 1 restarts to execute the program, therefore, the trace can be executed without decreasing remarkably the processing speed by a buffer memory of a small capacity.