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[1] For details, see 7.3

◎Single bus data sample calculation

Example 1: 40 of the received data:

0000 0010

1001 0010

0000 0001

0000 1101

1010 001

High humidity

8

Low humidity 8 High temperature 8

Low temperature8 Parity bit

Calculated as follows:

0000 0010+1001 0010 +0000 0001+0000 1101= 1010 0010 (Parity bit)

Receive data is correct:

Humidity:0000 0010

1001 0010 = 0292H (hex) = 2×256 + 9× 6 + 2 = 658 => Humidity =

65.8% RH

Temperature:0000 0001 0000 1101 = 10DH (hex) = 1×256 + 0×16 + 13 = 269

=> Temperature = 26.9 ℃

◎Special Instructions:

When the temperature is below 0 ℃ temperature data for a top position.

Example One: -10.1 ℃ expressed as 1,000,000,001,100,101

Temperature: 0000 0000 0110 0101 = 0065H (hex) = 6×16 +5 = 101

=> Temperature = -10.1 ℃

Example Two: The received data 40:

0000 0010

1001 0010

0000 0001

0000 1101

1011 0010

High humidity 8

Low humidity 8

High temperature 8

Low temperature8

Parity bit

Calculated as follows:

0000 0010+1001 0010 +0000 0001+0000 1101=1010 0010≠1011 0010 (Parity error)

The received data is not correct, give up, again receiving data.

8.3.3 Single-bus communication timing

Hosts (MCU) sends a start signal (data bus SDA low for at least 800μs) After, AM2321

transition from sleep mode to high-speed mode. After completion, the master start signal, AM2321

Name

Single bus format definition

Start signal

The microprocessor data bus (SDA) low period (at least 800μs)

, to prepare the data

notification sensor

Response signal

Sensor data bus (SDA) low 80μs, 80μs followed by a high signal in response to the initial host

Data Format

Upon receipt of the host start signal from the data bus disposable sensor (SDA) string of 40-bit

data, the high first-out

Humidity

Humidity resolution is 16Bit, the previous high; strings out of the humidity sensor is 10 times the

actual humidity values.

Temperature

Temperature resolution is 16Bit, the previous high; sensor string temperature value is 10 times the

actual temperature value;

Temperature highest bit (Bit15) is equal to 1 indicates a negative temperature, the temperature

highest bit (Bit15) is equal to 0 indicates a positive temperature;

In addition to the temperature of the highest bit (Bit14 ~ Bit0) indicates the temperature value.

Parity bit

Parity bit = humidity high temperature + humidity + high + low temperature low

]

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