kD9561 CK9561 Four-tone alarm sound chip music IC music integrated block
There are four kinds of alarm sounds, in fact only three are used, namely 110** alarm sound, 119 fire alarm sound, 120 medical rescue sound, and the other machine gun sound is mainly used for toy guns.
Sound effect selection sound termination method
SEL1/K1 - SEL2/K2
Alarm whistle : SEL1=NC - SEL2=NC
Fire alarm : SEL1=VCC - SEL2=NC
Ambulance voice :SEL1=GND - SEL2=NC
Machine guns sound: SEL1=NC - SEL2=VCC