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5.3 DHT Responses to MCU (Figure 3, above)

Once DHT detects the start signal, it will send out a low-voltage-level response signal, which

lasts 80us. Then the programme of DHT sets Data Single-bus voltage level from low to high and

keeps it for 80us for DHT’s preparation for sending data.

When DATA Single-Bus is at the low voltage level, this means that DHT is sending the response

signal. Once DHT sent out the response signal, it pulls up voltage and keeps it for 80us and

prepares for data transmission.

When DHT is sending data to MCU, every bit of data begins with the 50us low-voltage-level and

the length of the following high-voltage-level signal determines whether data bit is "0" or "1"

(see Figures 4 and 5 below).

Figure 4 Data "0" Indication