Point-to-point setup in Arduino IDE

[Mattias]

Hi
I have purchased a couple of iLabs Challenger LoRa 433 Mhz. I am using Arduino IDE for development and have done the standard “blink”-example and added a temperature sensor DS18B20 – all Is working great.

However, I would now like to make a simple point-to-point transmission, say send “HelloWorld” from one unit to the other. I have installed the library LoRa from Sandeep Mistry.

Example below gives me the error message “Starting LoRa Failed”. Does anyone see what the problem is or has anyone done something similar P2P that you want to share?
Kind regards,
Mattias

// LoRa by Sandeep Mistry
#include <SPI.h>
#include <LoRa.h>
int counter = 0;

void setup() {
Serial.begin(9600);
while (!Serial);
Serial.println("LoRa Sender");
if (!LoRa.begin(466E6)) {
Serial.println("Starting LoRa failed!");
while (1);
}
}

void loop() {
Serial.print("Sending packet: ");
Serial.println(counter);
// send packet
LoRa.beginPacket();
LoRa.print("HelloWorld");
LoRa.print(counter);
LoRa.endPacket();
counter++;
delay(5000);
}

[Mattias]

I also tried your example "raw" example-code, but got an error on the line.
const lmic_pinmap *pPinMap = Arduino_LMIC::GetPinmap_ThisBoard();

Is the code not supporting the boards with 433Mhz?
Kind regards,
Mattias

[Mattias]

Hello iLabs,
Do you know if this could be the case? That the library doesn't support 433Mhz.
Kind regards,
Mattias

[Pontus]

Hi Mattias,

Sorry for the late response. I know for sure that the board is not defined in the list of directly supported boards and this may be causing your issues. I will have a look at it later this week and see if we can make an update.

/Pontus

[Mattias]

Hi Pontus,
Any news regarding this problem?
Best regards,
Mattias

[Pontus]

I have done a little more digging into this. Our fork of arduino-lmic seem to detect the board properly but as it does not yet support 433MHz frequencies it is not suitable for for developing actual LoRaWAN applications. I did look into what would be required to support 433MHz and it is a fairly big job with a lot of testing required which would take a significant amount of time.

When you tried Sandeeps library did you also update the pinmap in the LoRa.h file ?

Here's the pin mapping as seen by the arduino-lmic library.
const lmic_pinmap lmic_pins = {
.nss = RFM95W_SS,
.rxtx = LMIC_UNUSED_PIN,
.rst = RFM95W_RST,
.dio = {RFM95W_DIO0, RFM95W_DIO1, RFM95W_DIO2},
.rxtx_rx_active = 0,
.rssi_cal = 8,
.spi = &SPI1,
.spi_freq = 8000000,
};