SunFounder ESP32 Manual page 343

Available Pins IO13, IO12, IO14, IO27, IO26, IO25, IO33, IO32, IO15, IO2, IO0, IO4, IO5, IO18, IO19,
IO21, IO22, IO23
Schematic
When the IO14 output is high, after the 1K current limiting resistor (to protect the transistor), the S8050 (NPN transistor)
will conduct, so that the buzzer will sound.
The role of S8050 (NPN transistor) is to amplify the current and make the buzzer sound louder. In fact, you can also
connect the buzzer directly to IO14, but you will find that the buzzer sound is smaller.
Wiring
Two types of buzzers are included in the kit. We need to use active buzzer. Turn them around, the sealed back (not the
exposed PCB) is the one we want.
3.14. 3.1 Beep
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