SIGNAL DISCRIMINATION SYSTEM OR BUSY TONE AND SO ON

摘要

PURPOSE:To make it possible to discriminate various signals which will occur in the future, by monitoring the irregularity value of signal periods and discriminating signals as periodic signals other than sound when the irregularity value becomes lower than a rated value. CONSTITUTION:CPU 3 monitors through bus line 8 that the signal from waveform shaping circuit 2 is H-level or L-level. Then, the count result of the H level and the count result of the L level are stored at address 2 and address 3 in data temporary store memory 5 respectively. CPU 3 adds count results at addresses 2 and 3 in data temporary store memory 5 to operate the irregularity value and the average value for each period each time the level is changed. CPU 3 compares this operation result with the irregularity value which is stored in rated value setting memory 6 and dicriminates whether the operation result becomes lower than the rated value or not, and next, CPU 3 compares the periodic property of signals to dicriminate various signals.