Added support for INA219 current sensor

.gitignore

@@ -1,5 +1,6 @@
 my_config.h
 .vscode
+.pio
 .pioenvs
 .piolibdeps
 .vscode/.browse.c_cpp.db*

SigkSens/SigkSens.ino

@@ -35,6 +35,9 @@
 #ifdef ENABLE_SYSTEMHZ
   #include "src/sensors/systemHz/systemHz.h"
 #endif
+#ifdef ENABLE_INA219
+  #include "src/sensors/ina219/ina219.h"
+#endif
 
 #include "FSConfig.h"
 
@@ -115,6 +118,11 @@ void setupFromJson() {
   fromJson[(int)SensorType::bme280] =
     (fromJsonFunc)&(BME280SensorInfo::fromJson);
   #endif
+
+  #ifdef ENABLE_INA219
+  fromJson[(int)SensorType::ina219] =
+    (fromJsonFunc)&(INA219SensorInfo::fromJson);
+  #endif
 }
 
 // forward declarations

SigkSens/config.h

@@ -9,7 +9,7 @@ Feature selection
 
 // Print Deltas to Serial? when enabled deltas are also printed to Serial, to 
 // aid in debuging. If you do not want this comment this line out.
-#define ENABLE_SERIAL_DELTA
+ #define ENABLE_SERIAL_DELTA
 
 
 // To enable any of the features below, either uncomment out the row
@@ -32,6 +32,7 @@ Feature selection
 //#define ENABLE_BMP280
 //#define ENABLE_BME280
 //#define ENABLE_ADS1115
+//#define ENABLE_INA219
 
 // Services
 
@@ -106,6 +107,13 @@ Defines
 
 #define MPU_INTERRUPT_PIN 12 // D6 pin on Wemos D1 Mini
 
+// INA219 shunt setup
+
+#define SHUNT_AMP    200  // max ampere for shunt
+#define SHUNT_MV     75   // mV output at max amp
+#define MAX_VOLT     14.4 // max bus voltage (alternator/charge max)
+#define MAX_AMP      150  // max amp to be measured over shunt
+
 // Button configuration for resetting the device
 
 #define RESET_CONFIG_PIN 0

SigkSens/src/sensors/ina219/Adafruit_INA219_custom.cpp

@@ -0,0 +1,290 @@
+
+/*!
+ * @file Adafruit_INA219_custom.cpp
+ *
+ * @mainpage Adafruit INA219 current/power monitor IC
+ *
+ * @section intro_sec Introduction
+ *
+ *  Driver for the INA219 current sensor
+ *
+ *  This is a library for the Adafruit INA219 breakout
+ *  ----> https://www.adafruit.com/product/904
+ *
+ *  Adafruit invests time and resources providing this open source code,
+ *  please support Adafruit and open-source hardware by purchasing
+ *  products from Adafruit!
+ *
+ * @section author Author
+ *
+ * Written by Bryan Siepert and Kevin "KTOWN" Townsend for Adafruit Industries.
+ *
+ * @section license License
+ *
+ * BSD license, all text here must be included in any redistribution.
+ *
+ */
+
+#include "Arduino.h"
+#include "Adafruit_INA219_custom.h"
+#include <Wire.h>
+
+
+/*!
+ *  @brief  Instantiates a new INA219 class
+ *  @param addr the I2C address the device can be found on. Default is 0x40
+ */
+Adafruit_INA219_custom::Adafruit_INA219_custom(uint8_t addr) {
+  ina219_i2caddr = addr;
+  ina219_currentMultiplier_A = 0.0f;
+  ina219_powerMultiplier_W = 0.0f;
+}
+
+/*!
+ *  @brief  Sets up the HW (defaults to 32V and 2A for calibration values)
+ *  @param theWire the TwoWire object to use
+ *  @return true: success false: Failed to start I2C
+ */
+bool Adafruit_INA219_custom::begin(TwoWire *theWire) {
+  i2c_dev = new Adafruit_I2CDevice(ina219_i2caddr, theWire);
+
+  if (!i2c_dev->begin()) {
+    return false;
+  }
+  init();
+  return true;
+}
+
+/*!
+ *  @brief  begin I2C and set up the hardware
+ */
+void Adafruit_INA219_custom::init() {
+  // Set chip to large range config values to start
+}
+
+/*!
+ *  @brief  Checks if conversion is ready
+ *  @return return true if conversion is ready
+ */
+bool Adafruit_INA219_custom::conversionReady() {
+  uint16_t value;
+
+  Adafruit_BusIO_Register bus_voltage_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_BUSVOLTAGE, 2, MSBFIRST);
+  bus_voltage_reg.read(&value);
+
+  // Shift to the right 3 to drop CNVR and OVF and multiply by LSB
+  return (value & INA219_CNVR_MASK) != 0;
+}
+
+/*!
+ *  @brief  Gets the raw bus voltage (16-bit signed integer, so +-32767)
+ *  @return the raw bus voltage reading
+ */
+int16_t Adafruit_INA219_custom::getBusVoltage_raw() {
+  uint16_t value;
+
+  Adafruit_BusIO_Register bus_voltage_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_BUSVOLTAGE, 2, MSBFIRST);
+  bus_voltage_reg.read(&value);
+
+  // Shift to the right 3 to drop CNVR and OVF and multiply by LSB
+  return (int16_t)((value >> 3) * 4);
+}
+
+/*!
+ *  @brief  Gets the raw shunt voltage (16-bit signed integer, so +-32767)
+ *  @return the raw shunt voltage reading
+ */
+int16_t Adafruit_INA219_custom::getShuntVoltage_raw() {
+  uint16_t value;
+  Adafruit_BusIO_Register shunt_voltage_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_SHUNTVOLTAGE, 2, MSBFIRST);
+  shunt_voltage_reg.read(&value);
+  return value;
+}
+
+/*!
+ *  @brief  Gets the raw current value (16-bit signed integer, so +-32767)
+ *  @return the raw current reading
+ */
+int16_t Adafruit_INA219_custom::getCurrent_raw() {
+  uint16_t value;
+
+  // Sometimes a sharp load will reset the INA219, which will
+  // reset the cal register, meaning CURRENT and POWER will
+  // not be available ... avoid this by always setting a cal
+  // value even if it's an unfortunate extra step
+  Adafruit_BusIO_Register calibration_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_CALIBRATION, 2, MSBFIRST);
+  calibration_reg.write(ina219_calValue, 2);
+
+  // Now we can safely read the CURRENT register!
+  Adafruit_BusIO_Register current_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_CURRENT, 2, MSBFIRST);
+  current_reg.read(&value);
+  return value;
+}
+
+/*!
+ *  @brief  Gets the raw power value (16-bit signed integer, so +-32767)
+ *  @return raw power reading
+ */
+int16_t Adafruit_INA219_custom::getPower_raw() {
+  uint16_t value;
+
+  // Sometimes a sharp load will reset the INA219, which will
+  // reset the cal register, meaning CURRENT and POWER will
+  // not be available ... avoid this by always setting a cal
+  // value even if it's an unfortunate extra step
+  Adafruit_BusIO_Register calibration_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_CALIBRATION, 2, MSBFIRST);
+  calibration_reg.write(ina219_calValue, 2);
+
+  // Now we can safely read the POWER register!
+  Adafruit_BusIO_Register power_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_POWER, 2, MSBFIRST);
+  power_reg.read(&value);
+  return value;
+}
+
+/*!
+ *  @brief  Triggers conversion
+ */
+void Adafruit_INA219_custom::triggerMeasurement() {
+  Adafruit_BusIO_Register config_reg = Adafruit_BusIO_Register(i2c_dev, INA219_REG_CONFIG, 2, MSBFIRST);
+  Adafruit_BusIO_RegisterBits mode_bits = Adafruit_BusIO_RegisterBits(&config_reg, 3, 0);
+  mode_bits.write(INA219_CONFIG_MODE_SANDBVOLT_TRIGGERED);
+}
+
+/*!
+ *  @brief  Gets the shunt voltage in mV (so +-327mV)
+ *  @return the shunt voltage converted to millivolts
+ */
+float Adafruit_INA219_custom::getShuntVoltage_mV() {
+  int16_t value;
+  value = getShuntVoltage_raw();
+  return value * 0.01;
+}
+
+/*!
+ *  @brief  Gets the shunt voltage in volts
+ *  @return the bus voltage converted to volts
+ */
+float Adafruit_INA219_custom::getBusVoltage_V() {
+  int16_t value = getBusVoltage_raw();
+  return value * 0.001;
+}
+
+/*!
+ *  @brief  Gets the current value in mA, taking into account the
+ *          config settings and current LSB
+ *  @return the current reading convereted to milliamps
+ */
+float Adafruit_INA219_custom::getCurrent_A() {
+  float valueDec = getCurrent_raw();
+  valueDec *= ina219_currentMultiplier_A;
+  return valueDec;
+}
+
+/*!
+ *  @brief  Gets the power value in mW, taking into account the
+ *          config settings and current LSB
+ *  @return power reading converted to milliwatts
+ */
+float Adafruit_INA219_custom::getPower_W() {
+  float valueDec = getPower_raw();
+  valueDec *= ina219_powerMultiplier_W;
+  return valueDec;
+}
+
+/*!
+ *  @brief  Set power save mode according to parameters
+ *  @param  on
+ *          boolean value
+ */
+void Adafruit_INA219_custom::powerSave(bool on) {
+  Adafruit_BusIO_Register config_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_CONFIG, 2, MSBFIRST);
+
+  Adafruit_BusIO_RegisterBits mode_bits =
+      Adafruit_BusIO_RegisterBits(&config_reg, 3, 0);
+  if (on) {
+    mode_bits.write(INA219_CONFIG_MODE_POWERDOWN);
+  } else {
+    mode_bits.write(INA219_CONFIG_MODE_SANDBVOLT_TRIGGERED);
+  }
+}
+
+/*!
+ *  @brief set device to alibration which uses the highest precision for
+ *     current measurement (0.1mA), at the expense of
+ *     only supporting 16V at 400mA max.
+ */
+bool Adafruit_INA219_custom::setCalibration(float shunt_A, float shunt_mV, float max_V, float max_A) {
+  // scale shunt values to working range
+  float scaled_mV = max_A/shunt_A * shunt_mV;
+
+  // set optimal PGA gain
+  uint16_t config_gain;
+  if (scaled_mV <= 40)
+    config_gain = INA219_CONFIG_GAIN_1_40MV; // Gain 1, 40mV Range
+  else if (scaled_mV <= 80)
+    config_gain = INA219_CONFIG_GAIN_2_80MV;  // Gain 2, 80mV Range
+  else if (scaled_mV <= 160)
+    config_gain = INA219_CONFIG_GAIN_4_160MV; // Gain 4, 160mV Range
+  else if (scaled_mV <= 320)
+    config_gain = INA219_CONFIG_GAIN_8_320MV; // Gain 8, 320mV Range
+  else
+    return false;
+
+  // set ADC range
+  uint16_t config_range;
+  if (max_V <= 16)
+    config_range = INA219_CONFIG_BVOLTAGERANGE_16V; // 0-16V Range
+  else if (max_V <= 32)
+    config_range = INA219_CONFIG_BVOLTAGERANGE_32V; // 0-32V Range
+  else
+    return false; // out of range
+
+  // calculate minimum LSB for adc
+  float shunt_r = shunt_mV/shunt_A/1000.;
+  float LSB_min = max_A/32768;
+
+  // round LSB to nearest factor 5
+  float LSB_factor = pow(10.0, 1-ceil(log10(LSB_min/5)))/5;
+  float LSB_round = ceil(LSB_min * LSB_factor) / LSB_factor;
+
+  // Set shunt calibration value
+  ina219_calValue = truncf(0.04096/(LSB_round*shunt_r));
+
+  // Set multipliers to convert raw current/power values
+  ina219_currentMultiplier_A = LSB_round;
+  ina219_powerMultiplier_W = 20. * LSB_round;
+
+  // Set Calibration register to 'Cal' calculated above
+  Adafruit_BusIO_Register calibration_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_CALIBRATION, 2, MSBFIRST);
+  calibration_reg.write(ina219_calValue, 2);
+  // Set Config register to take into account the settings above
+  uint16_t config = config_range |
+                    config_gain | INA219_CONFIG_BADCRES_12BIT |
+                    INA219_CONFIG_BADCRES_12BIT_128S_69MS;
+
+  Adafruit_BusIO_Register config_reg =
+      Adafruit_BusIO_Register(i2c_dev, INA219_REG_CONFIG, 2, MSBFIRST);
+  config_reg.write(config, 2);
+
+  Serial.print("INA219: ");
+  Serial.print(shunt_A,0);
+  Serial.print("A, ");
+  Serial.print(shunt_mV,0);
+  Serial.print("mV, ");
+  Serial.print(shunt_r*1000,3);
+  Serial.print("mOhm, ");
+  Serial.print(LSB_round*1000,2);
+  Serial.print("mA/bit, ");
+  Serial.print(ina219_calValue);
+  Serial.println("cal value");
+  return true;
+}