Node to Node communication on LoRa With ESP32
What is LoRa?
LoRa, short for long-range, is the physical layer or the wireless modulation utilized to create a long-range communication link. LoRa is based on Chirp Spread Spectrum (CSS) modulation, which maintains the same low power characteristics as FSK modulation but significantly increases the communication range.
Material Required is as follows:
- 2x LoRa Bee modules
- 2xESP32
- 1x Breadboard
- Jumper Wires
Circuit Diagram
Pin Details
LoRe BEE |
LoRe BEE physical pin |
ESP32 Pin |
MISO |
4 |
D19(MISO)
|
RESET |
5 |
D14 |
MOSI |
11 |
D23(MOSI) |
D0 |
12 |
D2 |
NSS |
17 |
D5 |
SCK |
18 |
D22(SCLK) |
3V3 |
1 |
3V3 |
GND |
10 |
GND |
Now we are going to set up LoRa Node to Node communication using ESP32. In Node to Node communication, we use two nodes. One of the nodes we configure as Transmitter and another node as Receiver
Step1: Installing ESP32 Add-on in Arduino IDE
To install the ESP32 board in your Arduino IDE, follow the steps given below
In your Arduino IDE, go to File> Preferences
Enter https://dl.espressif.com/dl/package_esp32_index.json into the “Additional Board Manager URLs” field as shown in the figure below.
Then, click the “OK” button
Go to Tools > Board > Boards Manager
Search ESP32 and Click on the install button
It should be installed after a few seconds.
Step2: Code And Library
Download as Zip file of Arduino-LoRa Library refer below link
https://www.arduino.cc/reference/en/libraries/lora/
Installing library
In the Arduino IDE, navigate to Sketch > Include Library > Add .ZIP Library.
At the top of the drop-down list, select the option to "Add. ZIP Library'' and choose the library zip file downloaded from the link given above.
Step 3: Sender Code
In your Arduino IDE, go to Tools > Board>ESP32 Arduino
Select your Board
Enter the following code and click on the Upload button in the Arduino IDE
#include <SPI.h>
#include <LoRa.h>
//define the pins used by the transceiver module
#define ss 5
#define rst 14
#define dio0 2
int counter = 0;
void setup() {
//initialize Serial Monitor
Serial.begin(115200);
while (!Serial);
Serial.println("LoRa Sender");
//setup LoRa transceiver module
LoRa.setPins(ss, rst, dio0);
//replace the LoRa.begin(---E-) argument with your location's frequency
//433E6 for Asia
//866E6 for Europe
//915E6 for North America
while (!LoRa.begin(866E6)) {
Serial.println(".");
delay(500);
}
// Change sync word (0xF3) to match the receiver
// The sync word assures you don't get LoRa messages from other LoRa transceivers
// ranges from 0-0xFF
LoRa.setSyncWord(0xF3);
Serial.println("LoRa Initializing OK!");
}
void loop() {
Serial.print("Sending packet: ");
Serial.println(counter);
//Send LoRa packet to the receiver
LoRa.beginPacket();
LoRa.print("hello ");
LoRa.print(counter);
LoRa.endPacket();
counter++;
delay(10000);
}
Once the code is uploaded, open the Arduino Serial monitor
Step 4: Receiver Code
In your Arduino IDE, go to Tools > Board>ESP32 Arduino
Select your Board
Enter the following code and click on the Upload button in the Arduino IDE
#include <SPI.h>
#include <LoRa.h>
//define the pins used by the transceiver module
#define ss 5
#define rst 14
#define dio0 2
void setup() {
//initialize Serial Monitor
Serial.begin(115200);
while (!Serial);
Serial.println("LoRa Receiver");
//setup LoRa transceiver module
LoRa.setPins(ss, rst, dio0);
//replace the LoRa.begin(---E-) argument with your location's frequency
//433E6 for Asia
//866E6 for Europe
//915E6 for North America
while (!LoRa.begin(866E6)) {
Serial.println(".");
delay(500);
}
// Change sync word (0xF3) to match the receiver
// The sync word assures you don't get LoRa messages from other LoRa transceivers
// ranges from 0-0xFF
LoRa.setSyncWord(0xF3);
Serial.println("LoRa Initializing OK!");
}
void loop() {
// try to parse packet
int packetSize = LoRa.parsePacket();
if (packetSize) {
// received a packet
Serial.print("Received packet '");
// read packet
while (LoRa.available()) {
String LoRaData = LoRa.readString();
Serial.print(LoRaData);
}
// print RSSI of packet
Serial.print("' with RSSI ");
Serial.println(LoRa.packetRssi());
}
}
Once the upload is complete, open the Arduino Serial monitor
On the receiver, you can see the packet transmitted by the transmitter.
Troubleshooting
After uploading code if you are not receiving any packet into the receiver node follow the below steps
1.Make sure both node sender and receiver are working the same
Frequency. Check the following lines in both the codes:
while (!LoRa.begin(866E6))
2. Ensure that the Serial Monitor is using a bad rate of 115200.
3. Check all connections to ensure they are correct.