Reference course: LoRa Describes how to connect a T/H sensor.

Click the product name to go to the product configuration page. Under User-defined Function, click Create Function to customize product functions.

On the device development page, adjust device data parsing as needed. Because LoRa resources are limited, the device is not suitable for directly transmitting JSON data. Therefore, you can use Device Data Parsing to convert original device data to PRODUCT JSON data.

The main function of the script for upstream data parsing is RawToProtocol, which takes fPort and bytes:

• FPort: Indicates the fPort field of LoRaWAN data reported by the device.
• Bytes: indicates the FRMPayload field of LoRaWAN data reported by the device.
• The output parameter of the script main function is an object in the product data template protocol format.

In the upstream data parsing section, the javascript sample code is as follows:

function RawToProtocol(fPort, bytes) {
    var data = {
        "method": "report"."clientToken" : new Date(),
        "params": {}}; data.params.temperature = bytes[0];
    data.params.humidity = bytes[1];
    data.params.period = bytes[2] | (bytes[3] < <8);
    return data;
}
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The main protocol function of downstream data parsing is ProtocolToRaw, where the input parameter is an object of the product data template protocol format and the output parameter is an array of at least 3 bytes:

• Byte 1: The FPort field of LoRaWAN protocol data sent to the device.
• Byte 2: bytes indicates the MType of LoRaWAN Data sent to the device. 0 indicates Unconfirmed Data Down, and 1 indicates Confirmed Data Down.
• Byte 3: starts the FRMPayload field of LoRaWAN protocol data sent to the device.

In the downstream data parsing section, the javascript sample code is as follows:

function ProtocolToRaw(obj) {
    var data = new Array(a); data[0] = 5;// fport=5
    data[1] = 0;// unconfirmed mode
    data[2] = obj.params.period & 0x00FF;
    data[3] = (obj.params.period >> 8) & 0x00FF;
    return data;
}
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The configuration is as follows:

On the device debugging page, click “New Device”. The device name dev001 and DevEUI can be obtained from the sticker on the back of LoRa node development board.

Power on and configure the gateway according to the method described in SECTION 01 – LoRa Gateway Configuration View and Modify Method (ST P-nucleo-Lrwan3 suite is used as an example). Configure the connection between the gateway and Tencent cloud as follows:

Adjust the frequency point information to 486.3mhZ-487.7mhz, and modify the instruction as follows (need to send one by one) :

AT + CH = 0486.3, A AT + CH = 1486, A AT + CH = 2486.7, A AT + CH = 3486.9, A AT + CH = 4487 2 PCT, B AT + CH = 5487.3, AT + CH = 6487 B, B The AT + CH = 7487.7, B AT + CH = 8, OFF the AT + CH = 9, OFFCopy the code

After all configurations, the information is shown as follows:

After the configuration is complete, run the following command to restart the module. After the restart, the module automatically obtains an IP address and connects to the server:

AT+RESET
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Download the source code from TencentOS Tiny’s official open source repository, go to the < tencentos-Tiny \board\NUCLEO_STM32L073RZ\KEIL\lorawan> directory and open the Tencentos_tiny. uvprojx project. Example projects include STM32L073 peripheral driver, TencentOS Tiny kernel, AT framework, RHF76 LoRaWAN module driver, LoRaWAN example cases.

• (1) to modify the\examples\LoRaWAN\lora_demo.c:

tos_lora_module_join_otaa("< fill DevEUI >"."< fill AppKey >");
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• (2) modified\devices\rhf76_lora\RHF76.h:

#define RHF76_ATCMD_SET_CHANNEL                 "at+ch=num,0-7\r\n"
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Since the 80-87 channel is planned for this example, adjust to:

#define RHF76_ATCMD_SET_CHANNEL                 "at+ch=num,80-87\r\n"
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After compiling and downloading the project, the node automatically restarts after downloading the firmware. You can view the run logs from the serial port.

If the following log is displayed on the serial port, the LoRa node is successfully connected to the network through the gateway:

--->+JOIN: Network joined
--->+JOIN: NetID 000035 DevAddr 6A:40:DA:3F
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You can see it in serial Assistant:

In this example, the LoRa node is A LoRaWAN Class A device. The device does not deliver data immediately. The server downlinks data to the device only after data is upstream. Therefore, you can view the delivered cycle adjustment commands only after the LoRa node reports data.