Fork of the espurna firmware for `mhsw` switches
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// -----------------------------------------------------------------------------
// Abstract Energy Monitor Sensor (other EMON sensors extend this class)
// Copyright (C) 2017-2018 by Xose Pérez <xose dot perez at gmail dot com>
// -----------------------------------------------------------------------------
#if SENSOR_SUPPORT
#pragma once
#undef I2C_SUPPORT
#define I2C_SUPPORT 1 // Explicitly request I2C support.
#include "Arduino.h"
#include "I2CSensor.h"
extern "C" {
#include "libs/fs_math.h"
}
class EmonSensor : public I2CSensor {
public:
// ---------------------------------------------------------------------
// Public
// ---------------------------------------------------------------------
EmonSensor(): I2CSensor() {
// Calculate # of magnitudes
#if EMON_REPORT_CURRENT
++_magnitudes;
#endif
#if EMON_REPORT_POWER
++_magnitudes;
#endif
#if EMON_REPORT_ENERGY
++_magnitudes;
#endif
}
void expectedPower(unsigned char channel, unsigned int expected) {
if (channel >= _channels) return;
unsigned int actual = _current[channel] * _voltage;
if (actual == 0) return;
if (expected == actual) return;
_current_ratio[channel] = _current_ratio[channel] * ((double) expected / (double) actual);
calculateFactors(channel);
_dirty = true;
}
void resetEnergy() {
for (unsigned char i=0; i<_channels; i++) {
_energy[i] = 0;
}
}
// ---------------------------------------------------------------------
void setVoltage(double voltage) {
if (_voltage == voltage) return;
_voltage = voltage;
_dirty = true;
}
void setReference(double reference) {
if (_reference == reference) return;
_reference = reference;
_dirty = true;
}
void setCurrentRatio(unsigned char channel, double current_ratio) {
if (channel >= _channels) return;
if (_current_ratio[channel] == current_ratio) return;
_current_ratio[channel] = current_ratio;
calculateFactors(channel);
_dirty = true;
}
// ---------------------------------------------------------------------
double getVoltage() {
return _voltage;
}
double getReference() {
return _reference;
}
double getCurrentRatio(unsigned char channel) {
if (channel >= _channels) return 0;
return _current_ratio[channel];
}
unsigned char getChannels() {
return _channels;
}
// ---------------------------------------------------------------------
// Sensor API
// ---------------------------------------------------------------------
void begin() {
// Resolution
_adc_counts = 1 << _resolution;
// Calculations
for (unsigned char i=0; i<_channels; i++) {
_energy[i] = _current[i] = 0;
_pivot[i] = _adc_counts >> 1;
calculateFactors(i);
}
#if SENSOR_DEBUG
DEBUG_MSG("[EMON] Reference (mV): %d\n", int(1000 * _reference));
DEBUG_MSG("[EMON] ADC counts: %d\n", _adc_counts);
for (unsigned char i=0; i<_channels; i++) {
DEBUG_MSG("[EMON] Channel #%d current ratio (mA/V): %d\n", i, int(1000 * _current_ratio[i]));
DEBUG_MSG("[EMON] Channel #%d current factor (mA/bit): %d\n", i, int(1000 * _current_factor[i]));
DEBUG_MSG("[EMON] Channel #%d Multiplier: %d\n", i, int(_multiplier[i]));
}
#endif
_ready = true;
_dirty = false;
}
protected:
// ---------------------------------------------------------------------
// Protected
// ---------------------------------------------------------------------
// Initializes internal variables
void init() {
_current_ratio = new double[_channels];
_current_factor = new double[_channels];
_multiplier = new uint16_t[_channels];
_pivot = new double[_channels];
_current = new double[_channels];
#if EMON_REPORT_ENERGY
_energy = new uint32_t[_channels];
#endif
}
virtual unsigned int readADC(unsigned char channel) = 0;
void calculateFactors(unsigned char channel) {
_current_factor[channel] = _current_ratio[channel] * _reference / _adc_counts;
unsigned int s = 1;
unsigned int i = 1;
unsigned int m = 1;
unsigned int multiplier = 1;
while (m * _current_factor[channel] < 1) {
multiplier = m;
i = (i == 1) ? 2 : (i == 2) ? 5 : 1;
if (i == 1) s *= 10;
m = s * i;
}
_multiplier[channel] = multiplier;
}
double read(unsigned char channel) {
int max = 0;
int min = _adc_counts;
double sum = 0;
unsigned long time_span = millis();
for (unsigned long i=0; i<_samples; i++) {
int sample;
double filtered;
// Read analog value
sample = readADC(channel);
if (sample > max) max = sample;
if (sample < min) min = sample;
// Digital low pass filter extracts the VDC offset
_pivot[channel] = (_pivot[channel] + (sample - _pivot[channel]) / EMON_FILTER_SPEED);
filtered = sample - _pivot[channel];
// Root-mean-square method
sum += (filtered * filtered);
}
time_span = millis() - time_span;
// Quick fix
if (_pivot[channel] < min || max < _pivot[channel]) {
_pivot[channel] = (max + min) / 2.0;
}
// Calculate current
double rms = _samples > 0 ? fs_sqrt(sum / _samples) : 0;
double current = _current_factor[channel] * rms;
current = (double) (int(current * _multiplier[channel]) - 1) / _multiplier[channel];
if (current < 0) current = 0;
#if SENSOR_DEBUG
DEBUG_MSG("[EMON] Channel: %d\n", channel);
DEBUG_MSG("[EMON] Total samples: %d\n", _samples);
DEBUG_MSG("[EMON] Total time (ms): %d\n", time_span);
DEBUG_MSG("[EMON] Sample frequency (Hz): %d\n", int(1000 * _samples / time_span));
DEBUG_MSG("[EMON] Max value: %d\n", max);
DEBUG_MSG("[EMON] Min value: %d\n", min);
DEBUG_MSG("[EMON] Midpoint value: %d\n", int(_pivot[channel]));
DEBUG_MSG("[EMON] RMS value: %d\n", int(rms));
DEBUG_MSG("[EMON] Current (mA): %d\n", int(1000 * current));
#endif
// Check timing
if ((time_span > EMON_MAX_TIME)
|| ((time_span < EMON_MAX_TIME) && (_samples < EMON_MAX_SAMPLES))) {
_samples = (_samples * EMON_MAX_TIME) / time_span;
}
return current;
}
unsigned char _channels = 0; // Number of ADC channels available
unsigned char _magnitudes = 0; // Number of magnitudes per channel
unsigned long _samples = EMON_MAX_SAMPLES; // Samples (dynamically modificable)
unsigned char _resolution = 10; // ADC resolution in bits
unsigned long _adc_counts; // Max count
double _voltage = EMON_MAINS_VOLTAGE; // Mains voltage
double _reference = EMON_REFERENCE_VOLTAGE; // ADC reference voltage (100%)
double * _current_ratio; // Ratio ampers in main loop to voltage in secondary (per channel)
double * _current_factor; // Calculated, reads (RMS) to current (per channel)
uint16_t * _multiplier; // Calculated, error (per channel)
double * _pivot; // Moving average mid point (per channel)
double * _current; // Last current reading (per channel)
#if EMON_REPORT_ENERGY
uint32_t * _energy; // Aggregated energy (per channel)
#endif
};
#endif // SENSOR_SUPPORT