Aosong Electronics Co.,Ltd

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Your specialist in innovating humidity & temperature sensors

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Host computer send start signal

Sensor send out response signal

and keep this signal at least 1ms

and keep this signal 80us

Host pull up voltage

-and wait sensor's response

Sensor pull up bus's voltage

Signal from host

Start data transmission

Signal from sensor

Single-bus signal

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Step 2: DHT22 send response signal to MCU

When DHT22 detect the start signal, DHT22 will send out low-voltage-level signal and this signal last 80us as

response signal, then program of DHT22 transform data-bus's voltage level from low to high level and last 80us

for DHT22's preparation to send data.

Check bellow picture for step 2:

Thomas Liu (Business Manager)

Email: thomasliu198518@yahoo.com.cn

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