Hello everyone! Today I want to introduce a very practical Python library for IoT development – LoraGateway. It is an open-source library specifically designed for handling LoRa communication, helping us easily achieve long-distance wireless communication between devices. I wonder if anyone has experience with IoT development? Let’s explore this powerful tool together!
1. Hardware Connection
1. Introduction to Connection Methods
The LoRa module typically connects to a single-board computer (like Raspberry Pi) using the SPI interface. The specific connection pins include MOSI, MISO, SCK, NSS, DIO0, VCC, and GND. Taking the Raspberry Pi as an example for building a LoRa gateway, insert the MicroSD card into the Raspberry Pi and connect the SX130x 868M LoRaWAN gateway module to the GPIO pins of the Raspberry Pi, ensuring the pins are correctly aligned and the module is securely connected. Then, install the operating system on the Raspberry Pi, using the Raspberry Pi imaging software to download and install the 32-bit Lite version of the operating system, setting up the WiFi and SSH options for the SD card. After assembling and inserting the SD card, turn on the Raspberry Pi power, use Angry IP Scanner software to determine the IP address of the Raspberry Pi, and log in to the IP address using bitvise ssh software to establish an SSH connection. Next, use the command ‘Raspi-config’ to enable SPI, serial, and I2C, and configure the Raspberry Pi. Finally, install the SX1302 gateway binary file, verify the hardware connection, and start the LoRa concentrator mask while providing configuration files to achieve data reception.
For communication between Python and the LoRa module, assuming the connection pins are as follows: LoRa module pins Raspberry Pi pins are MOSI GPIO 10, MISO GPIO 9, SCK GPIO 11, NSS GPIO 8, DIO0 GPIO 24, VCC 3.3V, GND GND. During the hardware connection process, ensure the interfaces are properly connected, check if the two-color light is functioning normally, and if not lit, it may be due to poor contact or module damage. You can also check the COM port through the device manager, selecting the correct COM port to ensure the LoRa module can connect to the computer for parameter settings. At the same time, when transmitting LORA data between STM32 and Raspberry Pi, STM32 connects to the LORA module via serial port 2, while the Raspberry Pi connects to the LORA module via the SPI interface; the specific connection method can refer to detailed descriptions in relevant materials. Additionally, when setting up a data transparent transmission server, it is also necessary to consider establishing a physical connection between the transparent transmission server and LORA devices; a common connection method is via serial port, where you can use a serial cable to connect the server and devices. When configuring the server, you need to set the serial communication parameters to correctly read data from the devices.
2. Basic Code Examples
1. Sending Data
Use ‘from lora import LoRa’ to import the module, create a LoRa object, set the mode and frequency, send a message, and print the sent content. Here is a specific code example:
from lora import LoRa
lora = LoRa()
lora.set_mode_lora()
lora.set_frequency(915E6) # Set frequency to 915MHz
message = "Hello, LoRa!"
lora.send(message)
print(f"Sent: {message}")
2. Receiving Data
Similarly, create a LoRa object, set the mode and frequency, loop to receive data packets, read the data, and print the received content. Here is the code example for receiving data:
from lora import LoRa
lora = LoRa()
lora.set_mode_lora()
lora.set_frequency(915E6) # Set frequency to 915MHz
while True:
if lora.received_packet():
data = lora.read_packet()
print(f"Received: {data.decode()}")
3. Class Diagram and Sequence Diagram
1. The class diagram displays the methods of the LoRa class, including set_mode_lora, set_frequency, send, received_packet, and read_packet.
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set_mode_lora: Used to set the working mode of LoRa.
The class diagram helps us better understand the main classes and their relationships in the system. For the LoRa communication system, we can draw a class diagram to show the structure and methods of the LoRa class.
The LoRa class contains the following methods:
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set_frequency: Used to set the frequency of LoRa.
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send: Used to send data.
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received_packet: Used to check if a data packet has been received.
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read_packet: Used to read the received data packet.
Here is an example of a class diagram for the LoRa class:
classDiagram
class LoRa {
+set_mode_lora()
+set_frequency(freq)
+send(message)
+received_packet()
+read_packet()
}
2. The sequence diagram displays the sequential flow of sending and receiving data, involving three participants: Sender, LoRaModule, and Receiver.
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Sender calls the set_mode_lora method of LoRaModule to set the working mode of LoRa.
The sequence diagram can showcase the sequential flow of sending and receiving data, helping us better understand the interaction process of the system. For the LoRa communication system, we can draw a sequence diagram to illustrate the interaction between the Sender, LoRaModule, and Receiver.
The sequential flow for sending data is as follows:
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Sender calls the set_frequency method of LoRaModule to set the frequency of LoRa.
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Sender calls the send method of LoRaModule to send data.
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LoRaModule sends the data and returns Message Sent to Sender.
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Receiver calls the received_packet method of LoRaModule to check if a data packet has been received.
The sequential flow for receiving data is as follows:
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If a data packet is received, Receiver calls the read_packet method of LoRaModule to read the data packet.
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LoRaModule returns the read data to Receiver.
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Receiver prints the received data.
Here is an example of a sequence diagram for a LoRa communication system:
1 sequenceDiagram
participant Sender
participant LoRaModule
participant Receiver
Sender->>LoRaModule: set_mode_lora()
Sender->>LoRaModule: send(message)
LoRaModule-->>Sender: Message Sent
Receiver->>LoRaModule: received_packet()
LoRaModule-->>Receiver: read_packet()
Receiver-->>Receiver: Print data