SEMICONDUCTOR INTEGRATED CIRCUIT AND DEVICE SIGNAL OBSERVATION SYSTEM

PROBLEM TO BE SOLVED: To easily observe a signal of an ASIC in a device loaded with the ASIC, and to improve debugging work efficiency. SOLUTION: This system has a constitution wherein a signal for designating the ASIC (semiconductor integrated circuit) which is a signal observation object outputted from a CPU 13 (central processing unit) is received, and a present signal level of a pin of the signal observation object designated as the signal observation object and a signal level when the signal level is changed are stored in a signal observation pin level register 413 obtainably by the CPU 13, and in the case where the signal level of the pin of the signal observation object is changed, when the CPU 13 receives an interruption signal outputted from an interruption signal generation part 44, the CPU 13 obtains the signal level stored in the signal observation pin level register 413 and displays it on a display part 12. COPYRIGHT: (C)2005,JPO&NCIPI