Added INA233

lib/INA233/INA233.cpp

@@ -0,0 +1,82 @@
+#include "INA233.h"
+
+INA233::INA233(const uint8_t address, TwoWire *wire)
+{
+  _address     = address;
+  _wire        = wire;
+  //  not calibrated values by default.
+  _current_LSB = 0;
+  _maxCurrent  = 0;
+  _shunt       = 0;
+}
+
+bool INA233::begin(const uint8_t sda, const uint8_t scl)
+{
+  _wire->begin(sda, scl);
+  if (! isConnected()) return false;
+  return true;
+}
+
+bool INA233::isConnected()
+{
+  _wire->beginTransmission(_address);
+  return ( _wire->endTransmission() == 0);
+}
+
+float INA233::getBusVoltage() {
+    uint8_t data[2];
+    int16_t rawVoltage;
+
+    // Request data from the PMBus device
+    Wire.beginTransmission(INA233::_address);
+    Wire.write(REGISTER_READ_VIN);
+    Wire.endTransmission();
+    Wire.requestFrom(INA233::_address, 2);
+
+    if (Wire.available() == 2) {
+        data[0] = Wire.read();
+        data[1] = Wire.read();
+    } else {
+        // Handle error (e.g., return 0.0 or a special error value)
+        return 0.0;
+    }
+
+    // Combine the two bytes into a single 16-bit value
+    rawVoltage = (data[1] << 8) | data[0];
+
+    // Convert raw value to actual voltage using the appropriate scaling
+    // For example, assuming a linear scaling with a coefficient of 1.25 mV per LSB:
+    float voltage = rawVoltage * 1.25 / 1000.0;
+
+    return voltage;
+}
+
+float INA233::getShuntVoltage() {
+    uint8_t data[2];
+    int16_t rawVoltage;
+
+    // Request data from the PMBus device
+    Wire.beginTransmission(INA233::_address);
+    Wire.write(REGISTER_READ_VSHUNT);
+    Wire.endTransmission();
+    Wire.requestFrom(INA233::_address, 2);
+
+    if (Wire.available() == 2) {
+        data[0] = Wire.read();
+        data[1] = Wire.read();
+    } else {
+        // return 0 on error
+        return 0.0;
+    }
+
+    // Combine the two bytes into a single 16-bit value
+    rawVoltage = (data[1] << 8) | data[0];
+
+    // convert it to volts
+    float voltage = rawVoltage * pow(10,-4);
+    return voltage;
+}
+
+float INA233::getShuntVoltage_mV() {
+    return getShuntVoltage() * 1000;
+}

lib/INA233/INA233.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include "Arduino.h"
+#include "Wire.h"
+
+
+#define REGISTER_READ_VIN 0x88
+#define REGISTER_READ_VSHUNT 0xd1
+
+class INA233{
+ public:
+  INA233(uint8_t addr, TwoWire *wire = &Wire);
+  bool begin(const uint8_t sda, const uint8_t scl);
+  float getBusVoltage(void);
+  float getShuntVoltage_mV(void);
+  float getShuntVoltage(void);
+  bool isConnected(void);
+
+ private:
+  float    _current_LSB;
+  float    _shunt;
+  float    _maxCurrent;
+
+  uint8_t   _address;
+  TwoWire * _wire;
+};