Raspberry pi to Raspberry pi LoRa sx1278 communication Via Arduino Esp32 Serial communication

Data Flow-    

RPI -> <- ESP32(Arduino) -> <- LoRa SX1278 -> -----<- LoRa SX1278-> <- ESP32(Arduino) -> <-RPI

Demo Video- https://youtu.be/7apXm8SlbFk?si=TTdfYNFo6x1Nw2ef

1. Enable Serial port with command- sudo raspi-config

     Interface Options → Serial Port → Enable

                       → Serial Login shell → Disable

     Login shell over serial? → No

     Enable serial port hardware? → Yes

     Command- sudo reboot

2. command- pip install pyserial  (if Needed)

3. port command- ls -l /dev/serial* /dev/ttyS* /dev/ttyAMA*

4.  Connection and Circuit diagram-

A. ESP32 ↔ Raspberry Pi (UART Communication)

Raspberry Pi GPIO	Connected to ESP32	Description
GPIO14 (TXD)	GPIO26 (RX)	RPi TX ➜ ESP32 RX
GPIO15 (RXD)	GPIO27 (TX)	RPi RX ⬅ ESP32 TX
GND	GND	Common ground

✅ You are using SoftwareSerial on ESP32 pins 26 (RX) and 27 (TX).

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B. ESP32 ↔ LoRa Module (SPI Communication)

LoRa Module	ESP32 GPIO	Function
MOSI	GPIO23	Master Out Slave In
MISO	GPIO19	Master In Slave Out
SCK	GPIO18	SPI Clock
NSS (CS)	GPIO5	Chip Select
RST	GPIO16	Reset Pin
DIO0	GPIO17	Interrupt / Ready
GND	GND	Common Ground
VCC	3.3V	Power Supply

✅ SPI communication is used for LoRa with LoRa.setPins(5, 16, 17).

   C. Connection Video- https://youtu.be/ZOXh5LQkJ4g?si=__kA2VGI2zA4Z-yJ