Barometric Pressure and Temperature Command

Tag 0x50-0x5f command for Barometric Pressure and Temperature function are explained in this page.

Keyword

NA: Not applicable, this command should no be sent by the sensor/application.

None: No data contained in this command, data length can be set to 0x00.

Tag 0x50

Meaning:

Start air pressure and temperature streaming. Measurement will continue until 0x51 stop command is called. Data reply with tag 0x56.

Data Format - Input:

Byte Length 1 1
Meaning ODR Average

ODR (Output Data Rate): Code listed below, set how many data output per second.

Average: Set how many data are averaging for each measurement.

ODR / Hz Code
1 0x01
4 0x02
10 0x03
25 0x04
50 0x05
75 0x06
100 0x07
200 0x08
Averaging Data Code Max ODR Support
4 0x00 500
8 0x01 400
16 0x02 300
32 0x03 200
64 0x04 100
128 0x05 75
512 0x07 25

Data Format - Output:

Same as send format. Same format will acknowledge after command is executed.

Tag 0x51

Meaning:

Stop air pressure and temperature streaming.

Data Format - Input:

None.

Data Format - Output:

Same as send format. Same format will acknowledge after command is executed.

Tag 0x56

Meaning:

Measured air pressure and temperature reply through streaming with this tag.

Data Format - Input:

NA.

Data Format - Output:

Byte Length 4 4 8 (optional)
Meaning Air Pressure Temperature Time Stamp

Air Pressure: Float with 4 bytes length. In the unit of Pa.

Temperature: Float with 4 bytes length. In the unit of degree Celsius.

Time Stamp: Unsigned Long, unit is 2.4414us. Represent the data record time. Only appear when the "with time stamp" format is chosen. This timer might not start from zero. Usually it is used to help synchronize data from multiple sensors or calculate the accurate data rate.

Tag 0x5A

Meaning:

Start air pressure and temperature offline record. Record data without Bluetooth connection.

Data Format - Input:

Byte Length 1 1 8
Meaning Period Stop Adv Current Unix Time
Period Code
1 min 0x01
2 min 0x02
3 min 0x03
5 min 0x05
10 min 0x0a
15 min 0x0f
30 min 0x1e
1 hour 0x3c
2 hour 0x3d
4 hour 0x40
8 hour 0x44

Stop Adv: Stop Advertising Code. If 0x01, BLE advertising will stop during recording for power saving, advertising reactivate on charging. If 0x00, advertising continue during recording.

Current Unix Time: Input the current Unix Time in second, in format of 8 bytes, for recording date and time calculation. If not use, can be entered as 0.

Sensor will auto disconnect and start recording after this command. Please wait for disconnect and don't send any other command after this command.

For data reading, refer to the Storage command page.

Data Format - Output:

Same as send format. Same format will acknowledge after command is executed.

Tag 0x5B

Meaning:

Stop air pressure and temperature offline recording.

Data Format - Input:

Byte Length 8
Meaning Current Unix Time

Current Unix Time: Input the current Unix Time in second, in format of 8 bytes, for recording date and time calculation. If not use, can be entered as 0.

Data Format - Output:

Same as send format. Same format will acknowledge after command is executed.