Datasheet

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clock, reading data, or communication error occurs.
Figure 17: Read the sample temperature and humidity values
Host read back the data as follows:
0x03(Function Code)+0x04(data length)+0x03(high humidity)+0x39(low humidity) +
0x01 (high temperature) +0x15(low temperature)+0xE1(CRC checksum low byte) + 0xFE
(CRC checksum high byte);
Therefore: 0339H = 3
×
256 +3
×
16 +9 = 825 => humidity = 825
÷
10 = 82.5% RH;
0115H = 1
×
256 +1
×
16 +5 = 277 => temperature = 277
÷
10 = 27.7
℃
These three steps can be completed by the sensor reads all registers, a write operation (the user
can write registers, only five, namely the status register, register four users, while the status register
can only be written separately, otherwise it will error) ; the user in the design, follow these three
steps must be fully read and write.
After sending the sensor data, trigger a temperature and humidity measurements; After the
measurement is completed, the recording temperature and humidity values, then completed a
communication, the sensor automatically goes to sleep; therefore, as long unread sensors
continuously read the second sensor, in the second reading of the temperature and humidity back to
the latest value (minimum interval of continuous reading 2S).
8.2.5 Peripheral read flowchart
AM2320 read I2 C sensor schematic flow diagram shown in Figure 18, we also provide sample
code reads C51, need to download the client, please visit our website (www.aosong.com) associated
download, this manual does not provide code instructions.