Circuit Documentation

Summary

This circuit involves an Arduino Nano and an Arduino UNO, both interfaced with various sensors and modules including LoRa Ra-02 SX1278, BMP280, and ADXL345. The circuit is powered by a 12V battery and a 5V battery, with voltage regulation provided by Mini-360 DC-DC Step Down Buck Converters. The Arduino Nano and Arduino UNO are programmed to handle the data from the sensors and communicate via LoRa modules.

Component List

Arduino Nano

• Description: A small, complete, and breadboard-friendly board based on the ATmega328P.
• Pins: D1/TX, D0/RX, RESET, GND, D2, D3, D4, D5, D6, D7, D8, D9, D10, D11/MOSI, D12/MISO, VIN, 5V, A7, A6, A5, A4, A3, A2, A1, A0, AREF, 3V3, D13/SCK

Arduino UNO

• Description: A microcontroller board based on the ATmega328P.
• Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0, A1, A2, A3, A4, A5, SCL, SDA, AREF, D13, D12, D11, D10, D9, D8, D7, D6, D5, D4, D3, D2, D1, D0

LoRa Ra-02 SX1278

• Description: A LoRa module for long-range communication.
• Pins: GND, NSS, MOSI, MISO, SCK, D105, DI04, 3.3V, RST, DI00, DI01, D102, DI03

BMP280

• Description: A barometric pressure sensor.
• Pins: SDO, CSB, SDA, SCL, GND, VCC

ADXL345

• Description: A 3-axis accelerometer.
• Pins: GND, VCC, CS, INT1, INT2, SDO, SDA, SCL

Mini-360 DC-DC Step Down Buck Converter

• Description: A voltage regulator to step down voltage.
• Pins: Input -, Input +, Output +, Output -

Mini 360 Buck Converter

• Description: Another voltage regulator to step down voltage.
• Pins: IN-, OUT-, OUT+, IN+

Battery 12V

• Description: A 12V battery for power supply.
• Pins: +, -

5V Battery

• Description: A 5V battery for power supply.
• Pins: positive, negative

Wiring Details

Arduino Nano

• D2 connected to LoRa Ra-02 SX1278 DI00
• D9 connected to LoRa Ra-02 SX1278 RST
• D10 connected to LoRa Ra-02 SX1278 NSS
• D11/MOSI connected to LoRa Ra-02 SX1278 MOSI
• D12/MISO connected to LoRa Ra-02 SX1278 MISO
• GND connected to LoRa Ra-02 SX1278 GND, Mini 360 Buck Converter OUT-
• 5V connected to Mini 360 Buck Converter OUT+
• A5 connected to ADXL345 SCL, BMP280 SCL
• A4 connected to ADXL345 SDA, BMP280 SDA
• D13/SCK connected to LoRa Ra-02 SX1278 SCK

Arduino UNO

• 3.3V connected to LoRa Ra-02 SX1278 3.3V
• 5V connected to 5V Battery positive
• GND connected to 5V Battery negative, LoRa Ra-02 SX1278 GND
• D13 connected to LoRa Ra-02 SX1278 SCK
• D12 connected to LoRa Ra-02 SX1278 MISO
• D11 connected to LoRa Ra-02 SX1278 MOSI
• D10 connected to LoRa Ra-02 SX1278 NSS
• D9 connected to LoRa Ra-02 SX1278 RST
• D2 connected to LoRa Ra-02 SX1278 DI00

LoRa Ra-02 SX1278

• DI00 connected to Arduino Nano D2, Arduino UNO D2
• RST connected to Arduino Nano D9, Arduino UNO D9
• NSS connected to Arduino Nano D10, Arduino UNO D10
• MOSI connected to Arduino Nano D11/MOSI, Arduino UNO D11
• MISO connected to Arduino Nano D12/MISO, Arduino UNO D12
• GND connected to Arduino Nano GND, Mini 360 Buck Converter OUT-, Arduino UNO GND
• 3.3V connected to ADXL345 VCC, Mini-360 DC-DC Step Down Buck Converter Output +, BMP280 VCC, Arduino UNO 3.3V
• SCK connected to Arduino Nano D13/SCK, Arduino UNO D13

BMP280

• SCL connected to Arduino Nano A5, ADXL345 SCL
• SDA connected to Arduino Nano A4, ADXL345 SDA
• GND connected to LoRa Ra-02 SX1278 GND, Mini-360 DC-DC Step Down Buck Converter Output -
• VCC connected to LoRa Ra-02 SX1278 3.3V, Mini-360 DC-DC Step Down Buck Converter Output +

ADXL345

• SCL connected to Arduino Nano A5, BMP280 SCL
• SDA connected to Arduino Nano A4, BMP280 SDA
• GND connected to LoRa Ra-02 SX1278 GND, Mini-360 DC-DC Step Down Buck Converter Output -
• VCC connected to LoRa Ra-02 SX1278 3.3V, Mini-360 DC-DC Step Down Buck Converter Output +

Mini-360 DC-DC Step Down Buck Converter

• Input + connected to Battery 12V +
• Input - connected to Battery 12V -
• Output + connected to LoRa Ra-02 SX1278 3.3V, ADXL345 VCC, BMP280 VCC
• Output - connected to LoRa Ra-02 SX1278 GND, ADXL345 GND, BMP280 GND

Mini 360 Buck Converter

• IN+ connected to Battery 12V +
• IN- connected to Battery 12V -
• OUT+ connected to Arduino Nano 5V
• OUT- connected to Arduino Nano GND, LoRa Ra-02 SX1278 GND

Battery 12V

• + connected to Mini-360 DC-DC Step Down Buck Converter Input +, Mini 360 Buck Converter IN+
• - connected to Mini-360 DC-DC Step Down Buck Converter Input -, Mini 360 Buck Converter IN-

5V Battery

• positive connected to Arduino UNO 5V
• negative connected to LoRa Ra-02 SX1278 GND, Arduino UNO GND

Documented Code

Arduino Nano Code

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

Arduino UNO Code

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

This documentation provides a comprehensive overview of the circuit, including a summary, detailed component list, wiring details, and the code for the microcontrollers.