LoRa communication between ESP8266 and RPi 3B+ - c++

Question

I have an ESP8266 and a RPI 3B+ both equipped with LoRa-02 (SX1278) modules. I'm trying to send a packet from the ESP to the RPi, but it's not working.
Please consider the following code snippet on ESP8266:
main.cpp
#include "loRaComms.h"
void setup() {
// sender
Serial.begin(115200);
initLoRa(434800000);
}
void loop() {
// sender
brodcastBuffer();
delay(1000);
}
loRaComms.cpp
#include <LoRa.h>
void initLoRa(int freq) {
LoRa.setPins(Lora_NSS, Lora_RESET, Lora_DIO0);
LoRa.setFrequency(freq);
LoRa.setSignalBandwidth(62500);
LoRa.setSpreadingFactor(12);
LoRa.setCodingRate4(8);
LoRa.setGain(0);
LoRa.setPreambleLength(6);
if (!LoRa.begin(freq)) {
// initialize ratio at 915 MHz 433E6 - Asia, 866E6 - Europe, 915E6 - North America
Serial.println("LoRa init failed.");
} else {
Serial.println("LoRa init succeeded.");
}
}
void brodcastBuffer() {
LoRa.beginPacket(); // start packet
LoRa.print("hello!");
LoRa.endPacket();
}
I have no problem with the ESP8266 code. I have tested this code with 2 ESP8266, one sender and one receiver, everything is working fine!
Now let's see the RPi 3B+ code. I have used [this repository][1] with its own sample code as follows:
void * rx_f(void *p) {
rxData *rx = (rxData *)p;
printf("rx done \n");
printf("CRC error: %d\n", rx->CRC);
printf("Data size: %d\n", rx->size);
printf("string: %s\n", rx->buf); // Data we've received
printf("RSSI: %d\n", rx->RSSI);
printf("SNR: %f\n", rx->SNR);
free(p);
return NULL;
}
int main() {
LoRa_ctl modem;
// See for typedefs, enumerations and there values in LoRa.h header file
modem.spiCS = 0; // Raspberry SPI CE pin number
modem.rx.callback = rx_f;
modem.eth.preambleLen = 6;
modem.eth.bw = BW62_5; // Bandwidth 62.5KHz
modem.eth.sf = SF12; // Spreading Factor 12
modem.eth.ecr = CR8; // Error coding rate CR4/8
modem.eth.freq = 434800000; // 434.8MHz
modem.eth.resetGpioN = 27; // GPIO4 on lora RESET pin
modem.eth.dio0GpioN = 17; // GPIO17 on lora DIO0 pin to control Rxdone and Txdone interrupts
modem.eth.outPower = OP20; // Output power
modem.eth.powerOutPin = PA_BOOST; // Power Amplifier pin
modem.eth.AGC = 1; // Auto Gain Control
modem.eth.OCP = 240; // 45 to 240 mA. 0 to turn off protection
modem.eth.implicitHeader = 0; // Explicit header mode
modem.eth.syncWord = 0x12;
printf("%d\n", modem.eth.bw);
printf("%d\n", modem.eth.ecr);
// For detail information about SF, Error Coding Rate, Explicit header, Bandwidth, AGC, Over current protection and other features refer to sx127x datasheet https:// www.semtech.com/uploads/documents/DS_SX127$
LoRa_begin(&modem);
LoRa_receive(&modem);
while (1) {
usleep(200000);
}
printf("end\n");
LoRa_end(&modem);
}```
But I can't receive anything on RPi. I also tested the ping pong sample on two RPi 3 and it didn't work.
Did I miss something here? I'm open to use any alternative library on RPi3, but I can only use C/C++ libraries. I've used the following pins:
raspi LoRa
GPIO27, pin13 RESET
GPIO17, pin 11 DIO0
MOSI (GPIO10, pin 19) MOSI
MISO (GPIO9, pin 21) MISO
CLK (GPIO11, pin 23) SCK
SPI_CE0 (GPIO8, pin 24) NSS
[1]: https://%20github.com/YandievRuslan/sx1278-LoRa-RaspberryPi.git

Answer 1

You can check your pin connection
The PI 3 MISO is GPIO09 and MOSI is GPIO10.
So you need change the pin connection to the following
raspi LoRa
MOSI (GPIO10, pin 19) MISO
MISO (GPIO9, pin 21) MOSI
Here is the introduction of SPI MOSI and MISO
https://www.analog.com/en/analog-dialogue/articles/introduction-to-spi-interface.html