Data Sheet

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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