0.1.1 INA229

Author: RobTillaart

libraries/INA229/CHANGELOG.md

@@ -6,6 +6,11 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 
+## [0.1.1] - 2025-01-30
+- fix #3, support for **int32 getShuntVoltageRAW()**
+- cache ADCrange to improve **getShuntVoltage()**
+- minor edits
+
 ## [0.1.0] - 2025-01-22
 - initial version, 
   - based upon INA228 (API) + INA239 (SPI)

libraries/INA229/INA229.cpp

@@ -1,6 +1,6 @@
 //    FILE: INA229.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.0
+// VERSION: 0.1.1
 //    DATE: 2025-01-22
 // PURPOSE: Arduino library for the INA229, SPI, 20 bit, voltage, current and power sensor.
 //     URL: https://github.com/RobTillaart/INA229
@@ -104,6 +104,8 @@ bool INA229::begin()
     digitalWrite(_dataOut, LOW);
     digitalWrite(_clock,   LOW);
   }
+
+  getADCRange();
   return true;
 }
 
@@ -127,7 +129,7 @@ float INA229::getShuntVoltage()
 {
   //  shunt_LSB depends on ADCRANGE in INA229_CONFIG register.
   float shunt_LSB = 312.5e-9;  //  312.5 nV
-  if (getADCRange() == 1)
+  if (_ADCRange == true)
   {
     shunt_LSB = 78.125e-9;     //  78.125 nV
   }
@@ -143,6 +145,18 @@ float INA229::getShuntVoltage()
   return voltage;
 }
 
+int32_t INA229::getShuntVoltageRAW()
+{
+  //  remove reserved bits.
+  uint32_t value = _readRegister(INA229_SHUNT_VOLTAGE, 3) >> 4;
+  //  handle negative values (20 bit)
+  if (value & 0x00080000)
+  {
+    value |= 0xFFF00000;
+  }
+  return (int32_t)value;
+}
+
 //  PAGE 24 + 8.1.2
 float INA229::getCurrent()
 {
@@ -176,7 +190,7 @@ float INA229::getTemperature()
 //  PAGE 24 + 8.1.2
 double INA229::getEnergy()
 {
-  //  read 40 bit unsigned as a double to prevent 64 bit ints
+  //  read 40 bit unsigned as a double to prevent 64 bit integers
   //  double might be 8 or 4 byte, depends on platform
   //  40 bit ==> O(10^12)
   double value = _readRegisterF(INA229_ENERGY, 5);
@@ -188,7 +202,7 @@ double INA229::getEnergy()
 //  PAGE 24 + 8.1.2
 double INA229::getCharge()
 {
-  //  read 40 bit unsigned as a float to prevent 64 bit ints
+  //  read 40 bit unsigned as a float to prevent 64 bit integers
   //  double might be 8 or 4 byte, depends on platform
   //  40 bit ==> O(10^12)
   double value = _readRegisterF(INA229_CHARGE, 5);
@@ -213,8 +227,8 @@ bool INA229::setAccumulation(uint8_t value)
 {
   if (value > 1) return false;
   uint16_t reg = _readRegister(INA229_CONFIG, 2);
-  reg &= ~INA229_CFG_RSTACC;
   if (value == 1) reg |= INA229_CFG_RSTACC;
+  else            reg &= ~INA229_CFG_RSTACC;
   _writeRegister(INA229_CONFIG, reg);
   return true;
 }
@@ -243,8 +257,8 @@ uint8_t INA229::getConversionDelay()
 void INA229::setTemperatureCompensation(bool on)
 {
   uint16_t value = _readRegister(INA229_CONFIG, 2);
-  value &= ~INA229_CFG_TEMPCOMP;
   if (on) value |= INA229_CFG_TEMPCOMP;
+  else    value &= ~INA229_CFG_TEMPCOMP;
   _writeRegister(INA229_CONFIG, value);
 }
 
@@ -257,16 +271,20 @@ bool INA229::getTemperatureCompensation()
 //  PAGE 20
 void INA229::setADCRange(bool flag)
 {
+  //  if (flag == _ADCRange) return;
+  _ADCRange = flag;
   uint16_t value = _readRegister(INA229_CONFIG, 2);
-  value &= ~INA229_CFG_ADCRANGE;
   if (flag) value |= INA229_CFG_ADCRANGE;
+  else      value &= ~INA229_CFG_ADCRANGE;
+  //  if value has not changed we do not need to write it back.
   _writeRegister(INA229_CONFIG, value);
 }
 
 bool INA229::getADCRange()
 {
   uint16_t value = _readRegister(INA229_CONFIG, 2);
-  return (value & INA229_CFG_ADCRANGE) > 0;
+  _ADCRange = (value & INA229_CFG_ADCRANGE) > 0;
+  return _ADCRange;
 }
 
 
@@ -372,7 +390,7 @@ int INA229::setMaxCurrentShunt(float maxCurrent, float shunt)
   //  PAGE 31 (8.1.2)
   float shunt_cal = 13107.2e6 * _current_LSB * _shunt;
   //  depends on ADCRANGE in INA229_CONFIG register.
-  if (getADCRange() == 1)
+  if (_ADCRange == true)
   {
     shunt_cal *= 4;
   }
@@ -598,7 +616,7 @@ bool INA229::usesHWSPI()
 
 ////////////////////////////////////////////////////////
 //
-//  SHOULD BE PROTECTED
+//  PRIVATE
 //
 uint32_t INA229::_readRegister(uint8_t reg, uint8_t bytes)  //  bytes = 2 or 3.
 {
@@ -692,11 +710,6 @@ uint16_t INA229::_writeRegister(uint8_t reg, uint16_t value)
 }
 
 
-/////////////////////////////////////////////////////////////////////////////
-//
-//  PROTECTED
-//
-
 uint8_t INA229::swSPI_transfer(uint8_t value)
 {
   uint8_t rv = 0;

libraries/INA229/INA229.h

@@ -1,7 +1,7 @@
 #pragma once
 //    FILE: INA229.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.1.0
+// VERSION: 0.1.1
 //    DATE: 2025-01-22
 // PURPOSE: Arduino library for the INA229, SPI, 20 bit, voltage, current and power sensor.
 //     URL: https://github.com/RobTillaart/INA229
@@ -13,7 +13,7 @@
 #include "SPI.h"
 
 
-#define INA229_LIB_VERSION          (F("0.1.0"))
+#define INA229_LIB_VERSION          (F("0.1.1"))
 
 
 #ifndef __SPI_CLASS__
@@ -123,6 +123,10 @@ class INA229
   float    getShuntMilliVolt()  { return getShuntVoltage() * 1e3; };
   float    getShuntMicroVolt()  { return getShuntVoltage() * 1e6; };
 
+  //  raw integer interface.
+  int32_t  getShuntVoltageRAW();
+
+
   //       SHUNT CURRENT
   float    getCurrent();        //  Ampere
   float    getAmpere()          { return getCurrent(); };
@@ -155,6 +159,7 @@ class INA229
   double   getCoulomb()         { return getCharge(); };
   double   getMilliCoulomb()    { return getCharge()       * 1e3; };
   double   getMicroCoulomb()    { return getCharge()       * 1e6; };
+
   //
   //  CONFIG REGISTER 0
   //  read datasheet for details, section 7.6.1.1, page 21
@@ -267,6 +272,7 @@ class INA229
   float    _current_LSB;
   float    _shunt;
   float    _maxCurrent;
+  bool     _ADCRange;
 
   uint8_t  _dataIn = 255;
   uint8_t  _dataOut= 255;

libraries/INA229/README.md

@@ -199,6 +199,8 @@ Note the value can be positive or negative as the INA229 is bidirectional.
 - **float getShuntVolt()**
 - **float getShuntMilliVolt()**
 - **float getShuntMicroVolt()**
+- **int32_t getShuntVoltageRAW()** integer version requested in issue #3.
+Returns raw ADC value, 20 bits with sign extended.
 
 ### SHUNT CURRENT