Base Dual 16340 Arduino Tutorial

#include "M5Unified.h"

// INA226 current/voltage monitor on internal I2C bus(M5.In_I2C)
// INA226 I2C address: 0x45
m5::INA226_Class Ina226(0x45);
bool ina226Ready = false;

void setup()
{
    auto cfg = M5.config();
    M5.begin(cfg);
    M5.Display.setFont(&fonts::FreeMonoBold9pt7b);

    // Initialize INA226 at I2C address 0x45
    if (Ina226.begin()) {
        ina226Ready = true;
        M5.Display.setCursor(10, 10);
        M5.Display.print("INA226 found!");

        // Configure INA226 measurement parameters
        m5::INA226_Class::config_t ina_cfg;

        // Shunt resistor value: 20mΩ (Fixed value for Base Dual 16340)
        ina_cfg.shunt_res = 0.02f;
        // Maximum expected current: 3A — used by the chip to set the calibration register
        ina_cfg.max_expected_current = 3.0f;
        // Operating mode: continuous measurement of both bus voltage and shunt voltage
        ina_cfg.mode = m5::INA226_Class::Mode::ShuntAndBus;
        // ADC sampling rate: average 16 samples per reading for noise reduction
        ina_cfg.sampling_rate = m5::INA226_Class::Sampling::Rate16;
        // Bus voltage conversion time: 1.1 ms per sample
        ina_cfg.bus_conversion_time = m5::INA226_Class::ConversionTime::US_1100;
        // Shunt voltage conversion time: 1.1 ms per sample
        ina_cfg.shunt_conversion_time = m5::INA226_Class::ConversionTime::US_1100;
        // Apply all configuration settings to the INA226
        Ina226.config(ina_cfg);
    } else {
        M5.Display.setCursor(10, 10);
        M5.Display.print("INA226 not found!");
    }
}

void loop()
{
    M5.update();
    M5.Display.clear();

    if (!ina226Ready) {
        M5.Display.setCursor(10, 10);
        M5.Display.print("INA226 not found!");
        delay(1000);
        return;
    }

    // VBUS is wired to BUS_BAT, so this is the battery output bus voltage.
    float batteryVoltage_V = Ina226.getBusVoltage();
    float batteryVoltage_mV = batteryVoltage_V * 1000.0f;
    M5.Display.setCursor(10, 10);
    M5.Display.printf("Battery Voltage: %.0fmV", batteryVoltage_mV);

    // Current through the shunt resistor is the battery current if no bypass path exists.
    float batteryCurrent_A = Ina226.getShuntCurrent();
    float batteryCurrent_mA = batteryCurrent_A * 1000.0f;
    M5.Display.setCursor(10, 40);
    M5.Display.printf("Battery Current: %.1fmA", batteryCurrent_mA);

    // Voltage drop across the 20mΩ shunt resistor.
    float shuntVoltage_mV = Ina226.getShuntVoltage() * 1000.0f;
    M5.Display.setCursor(10, 70);
    M5.Display.printf("Shunt Voltage: %.3fmV", shuntVoltage_mV);

    float shuntCurrent_mA = batteryCurrent_mA;
    M5.Display.setCursor(10, 100);
    M5.Display.printf("Shunt Current: %.1fmA", shuntCurrent_mA);

    // INA226 calculates power from bus voltage and calibrated shunt current.
    float batteryPower_mW = Ina226.getPower() * 1000.0f;
    M5.Display.setCursor(10, 130);
    M5.Display.printf("Battery Power: %.1fmW", batteryPower_mW);

    delay(1000);
}