NOTICE:
Before loading this code, you should not connect the KQM2801A and the DHT11,
If not, you may not load it successfully.
Hardware connection
KQM2801A ---- ESP32
5V -> 3V3
GND -> GND
A -> RX0
B -> TX0
DHT11 ----- ESP32
VCC -> 3V3
DATA -> D2
GND -> GND
OLED -------- ESP32
GND -> GND
VCC -> 3V3
SCL -> D22
SDA -> D21
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