88 lines
2.9 KiB
Arduino
88 lines
2.9 KiB
Arduino
|
/*
|
||
|
|
LoRa Duplex communication with Spreading Factor
|
||
|
|
|
||
|
|
Sends a message every half second, and polls continually
|
||
|
|
for new incoming messages. Sets the LoRa radio's spreading factor.
|
||
|
|
|
||
|
|
Spreading factor affects how far apart the radio's transmissions
|
||
|
|
are, across the available bandwidth. Radios with different spreading
|
||
|
|
factors will not receive each other's transmissions. This is one way you
|
||
|
|
can filter out radios you want to ignore, without making an addressing scheme.
|
||
|
|
|
||
|
|
Spreading factor affects reliability of transmission at high rates, however,
|
||
|
|
so avoid a hugh spreading factor when you're sending continually.
|
||
|
|
|
||
|
|
See the Semtech datasheet, http://www.semtech.com/images/datasheet/sx1276.pdf
|
||
|
|
for more on Spreading Factor.
|
||
|
|
|
||
|
|
created 28 April 2017
|
||
|
|
by Tom Igoe
|
||
|
|
*/
|
||
|
|
#include <SPI.h> // include libraries
|
||
|
|
#include <LoRa.h>
|
||
|
|
|
||
|
|
const int csPin = 7; // LoRa radio chip select
|
||
|
|
const int resetPin = 6; // LoRa radio reset
|
||
|
|
const int irqPin = 1; // change for your board; must be a hardware interrupt pin
|
||
|
|
|
||
|
|
byte msgCount = 0; // count of outgoing messages
|
||
|
|
int interval = 2000; // interval between sends
|
||
|
|
long lastSendTime = 0; // time of last packet send
|
||
|
|
|
||
|
|
void setup() {
|
||
|
|
Serial.begin(9600); // initialize serial
|
||
|
|
while (!Serial);
|
||
|
|
|
||
|
|
Serial.println("LoRa Duplex - Set spreading factor");
|
||
|
|
|
||
|
|
// override the default CS, reset, and IRQ pins (optional)
|
||
|
|
LoRa.setPins(csPin, resetPin, irqPin); // set CS, reset, IRQ pin
|
||
|
|
|
||
|
|
if (!LoRa.begin(915E6)) { // initialize ratio at 915 MHz
|
||
|
|
Serial.println("LoRa init failed. Check your connections.");
|
||
|
|
while (true); // if failed, do nothing
|
||
|
|
}
|
||
|
|
|
||
|
|
LoRa.setSpreadingFactor(8); // ranges from 6-12,default 7 see API docs
|
||
|
|
Serial.println("LoRa init succeeded.");
|
||
|
|
}
|
||
|
|
|
||
|
|
void loop() {
|
||
|
|
if (millis() - lastSendTime > interval) {
|
||
|
|
String message = "HeLoRa World! "; // send a message
|
||
|
|
message += msgCount;
|
||
|
|
sendMessage(message);
|
||
|
|
Serial.println("Sending " + message);
|
||
|
|
lastSendTime = millis(); // timestamp the message
|
||
|
|
interval = random(2000) + 1000; // 2-3 seconds
|
||
|
|
msgCount++;
|
||
|
|
}
|
||
|
|
|
||
|
|
// parse for a packet, and call onReceive with the result:
|
||
|
|
onReceive(LoRa.parsePacket());
|
||
|
|
}
|
||
|
|
|
||
|
|
void sendMessage(String outgoing) {
|
||
|
|
LoRa.beginPacket(); // start packet
|
||
|
|
LoRa.print(outgoing); // add payload
|
||
|
|
LoRa.endPacket(); // finish packet and send it
|
||
|
|
msgCount++; // increment message ID
|
||
|
|
}
|
||
|
|
|
||
|
|
void onReceive(int packetSize) {
|
||
|
|
if (packetSize == 0) return; // if there's no packet, return
|
||
|
|
|
||
|
|
// read packet header bytes:
|
||
|
|
String incoming = "";
|
||
|
|
|
||
|
|
while (LoRa.available()) {
|
||
|
|
incoming += (char)LoRa.read();
|
||
|
|
}
|
||
|
|
|
||
|
|
Serial.println("Message: " + incoming);
|
||
|
|
Serial.println("RSSI: " + String(LoRa.packetRssi()));
|
||
|
|
Serial.println("Snr: " + String(LoRa.packetSnr()));
|
||
|
|
Serial.println();
|
||
|
|
}
|
||
|
|
|