nymea-plugins/i2cdevices/ina219.cpp

212 lines
7.1 KiB
C++

// SPDX-License-Identifier: GPL-3.0-or-later
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* Copyright (C) 2013 - 2024, nymea GmbH
* Copyright (C) 2024 - 2025, chargebyte austria GmbH
*
* This file is part of nymea-plugins.
*
* nymea-plugins is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* nymea-plugins is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with nymea-plugins. If not, see <https://www.gnu.org/licenses/>.
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
#include "ina219.h"
#include <unistd.h>
#include <QtDebug>
#include <QThread>
#include <QDebug>
#include <QJsonDocument>
#include "extern-plugininfo.h"
#define INA219_REGISTER_CONFIGURATION 0x00
#define INA219_REGISTER_SHUNT_VOLTAGE 0x01
#define INA219_REGISTER_BUS_VOLTAGE 0x02
#define INA219_REGISTER_POWER 0x03
#define INA219_REGISTER_CURRENT 0x04
#define INA219_REGISTER_CALIBRATION 0x05
#define INA219_ADDRESS 0x80
#define INA219_READ 0x01
#define SHUNT_MILLIVOLTS_LSB 0.01 //# 10uV
#define BUS_MILLIVOLTS_LSB 4 // 4mV
#define CALIBRATION_FACTOR 0.04096
#define MAX_CALIBRATION_VALUE 0xFFFE // Max value supported (65534 decimal)
// # In the spec (p17) the current LSB factor for the minimum LSB is
// # documented as 32767, but a larger value (100.1% of 32767) is used
// # to guarantee that current overflow can always be detected.
#define CURRENT_LSB_FACTOR 32800
#define OVERFLOW_VALUE 1
#define INA219_CONFIG_BIT_RST 15
#define INA219_CONFIG_BIT_BRNG 13
#define INA219_CONFIG_BIT_PG1 12
#define INA219_CONFIG_BIT_PG0 11
#define INA219_CONFIG_BIT_BADC4 10
#define INA219_CONFIG_BIT_BADC3 9
#define INA219_CONFIG_BIT_BADC2 8
#define INA219_CONFIG_BIT_BADC1 7
#define INA219_CONFIG_BIT_SADC4 6
#define INA219_CONFIG_BIT_SADC3 5
#define INA219_CONFIG_BIT_SADC2 4
#define INA219_CONFIG_BIT_SADC1 3
#define INA219_CONFIG_BIT_MODE3 2
#define INA219_CONFIG_BIT_MODE2 1
#define INA219_CONFIG_BIT_MODE1 0
Ina219::Ina219(const QString &portName, int address, double shuntOhms, VoltageRange voltageRange, QObject *parent):
I2CDevice(portName, address, parent),
m_shuntOhms(shuntOhms),
m_voltageRange(voltageRange)
{
}
bool Ina219::writeData(int fileDescriptor, const QByteArray &data)
{
Q_UNUSED(data)
char buf[3] = {0};
// Calibration
double gain;
switch (m_gainVolts) {
case GainVolts032:
gain = 0.32;
break;
case GainVolts016:
gain = 0.16;
break;
case GainVolts008:
gain = 0.08;
break;
case GainVolts004:
default:
gain = 0.04;
break;
}
double maxPossibleAmps = gain / m_shuntOhms;
m_currentLSB = maxPossibleAmps / CURRENT_LSB_FACTOR;
quint16 calibration = CALIBRATION_FACTOR / (m_currentLSB * m_shuntOhms);
buf[0] = INA219_REGISTER_CALIBRATION;
buf[1] = calibration >> 8;
buf[2] = calibration & 0xFF;
qCDebug(dcI2cDevices()) << "INA219 writing calibration:" << QString::number(calibration, 16) << QByteArray(buf, 3).toHex();
int ret = write(fileDescriptor, buf, 3);
if (ret != 3) {
qCWarning(dcI2cDevices()) << "Failed to write calibration to INA219.";
return false;
}
// Configuration
quint16 configuration = m_voltageRange << INA219_CONFIG_BIT_BRNG;
configuration |= m_gainVolts << INA219_CONFIG_BIT_PG0;
configuration |= m_busADC << INA219_CONFIG_BIT_BADC1;
configuration |= m_shuntADC << INA219_CONFIG_BIT_SADC1;
configuration |= m_operationMode;
buf[0] = INA219_REGISTER_CONFIGURATION;
buf[1] = configuration >> 8;
buf[2] = configuration & 0xFF;
qCDebug(dcI2cDevices()) << "INA219 writing configuration:" << QString::number(configuration, 16) << QByteArray(buf, 3).toHex();
ret = write(fileDescriptor, buf, 3);
if (ret != 3) {
qCWarning(dcI2cDevices()) << "Failed to write configuration to INA219.";
return false;
}
return true;
}
QByteArray Ina219::readData(int fileDescriptor)
{
char buf[2] = {0};
buf[0] = INA219_REGISTER_SHUNT_VOLTAGE;
int ret = write(fileDescriptor, buf, 1);
if (ret != 1) {
qCWarning(dcI2cDevices()) << "Failed to select shunt voltage register on INA219";
return QByteArray();
}
ret = read(fileDescriptor, buf, 2);
if (ret != 2) {
qCWarning(dcI2cDevices()) << "Failed to read shunt voltage register on INA219";
return QByteArray();
}
int shuntVoltageRaw = ((buf[0] << 8) | buf[1]);
double shuntVoltage = shuntVoltageRaw * SHUNT_MILLIVOLTS_LSB / 1000;
buf[0] = INA219_REGISTER_BUS_VOLTAGE;
ret = write(fileDescriptor, buf, 1);
if (ret != 1) {
qCWarning(dcI2cDevices()) << "Failed to select bus voltage register on INA219";
return QByteArray();
}
ret = read(fileDescriptor, buf, 2);
if (ret != 2) {
qCWarning(dcI2cDevices()) << "Failed to read bus voltage register on INA219";
return QByteArray();
}
int busVoltageRaw = ((buf[0] << 8) | buf[1]);
bool overflow = (busVoltageRaw & OVERFLOW_VALUE) == 1;
busVoltageRaw = busVoltageRaw >> 3; // Registers are not right_aligned
double busVoltage = 1.0 * busVoltageRaw * BUS_MILLIVOLTS_LSB / 1000;
buf[0] = INA219_REGISTER_POWER;
ret = write(fileDescriptor, buf, 1);
if (ret != 1) {
qCWarning(dcI2cDevices()) << "Failed to select power register on INA219";
return QByteArray();
}
ret = read(fileDescriptor, buf, 2);
if (ret != 2) {
qCWarning(dcI2cDevices()) << "Failed to read power register on INA219";
return QByteArray();
}
int powerRaw = ((buf[0] << 8) | buf[1]);
double powerLSB = m_currentLSB * 20;
double power = powerRaw * powerLSB;
buf[0] = INA219_REGISTER_CURRENT;
ret = write(fileDescriptor, buf, 1);
if (ret != 1) {
qCWarning(dcI2cDevices()) << "Failed to select current register on INA219";
return QByteArray();
}
ret = read(fileDescriptor, buf, 2);
if (ret != 2) {
qCWarning(dcI2cDevices()) << "Failed to read current register on INA219";
return QByteArray();
}
int currentRaw = ((buf[0] << 8) | buf[1]);
double current = 1.0 * currentRaw * m_currentLSB;
qCDebug(dcI2cDevices()).nospace().noquote() << "INA219 Shunt voltage: " << shuntVoltage << "mV, Bus voltage: " << busVoltage << "V, Power: " << power << "W, Current: " << current << "A, Overflow: " << overflow;
QVariantMap readings;
readings.insert("shuntVoltage", shuntVoltage);
readings.insert("busVoltage", busVoltage);
readings.insert("power", power);
readings.insert("current", current);
readings.insert("overflow", overflow);
return QJsonDocument::fromVariant(readings).toJson(QJsonDocument::Compact);
}