Improve ADS1115 speed to 1450 SPS, keep separate pivot for each channel

code/espurna/config/sensors.h

@@ -143,7 +143,7 @@
 //--------------------------------------------------------------------------------
 
 #define EMON_MAX_SAMPLES            1000        // Max number of samples to get
-#define EMON_MAX_TIME               500         // Max time in ms to sample
+#define EMON_MAX_TIME               250         // Max time in ms to sample
 #define EMON_FILTER_SPEED           512         // Mobile average filter speed
 #define EMON_MAINS_VOLTAGE          230         // Mains voltage
 

code/espurna/sensors/EmonADC121Sensor.h

@@ -88,7 +88,7 @@ class EmonADC121Sensor : public EmonSensor {
             static unsigned long energy_delta = 0;
 
             if ((last == 0) || (millis() - last > 1000)) {
-                current = read(_address);
+                current = read(0, _pivot);
                 energy_delta = current * _voltage * (millis() - last) / 1000;
                 _energy += energy_delta;
                 last = millis();
@@ -113,17 +113,17 @@ class EmonADC121Sensor : public EmonSensor {
             #if I2C_USE_BRZO
                 uint8_t buffer[2];
                 buffer[0] = ADC121_REG_RESULT;
-                brzo_i2c_start_transaction(channel, I2C_SCL_FREQUENCY);
+                brzo_i2c_start_transaction(_address, I2C_SCL_FREQUENCY);
                 brzo_i2c_write(buffer, 1, false);
                 brzo_i2c_read(buffer, 2, false);
                 brzo_i2c_end_transaction();
                 value = (buffer[0] & 0x0F) << 8;
                 value |= buffer[1];
             #else
-                Wire.beginTransmission(channel);
+                Wire.beginTransmission(_address);
                 Wire.write(ADC121_REG_RESULT);
                 Wire.endTransmission();
-                Wire.requestFrom(channel, (unsigned char) 2);
+                Wire.requestFrom(_address, (unsigned char) 2);
                 value = (Wire.read() & 0x0F) << 8;
                 value = value + Wire.read();
             #endif
@@ -134,6 +134,6 @@ class EmonADC121Sensor : public EmonSensor {
 
         unsigned char _address;
         unsigned long _energy = 0;
-
+        double _pivot = 0;
 
 };

code/espurna/sensors/EmonADS1115Sensor.h

@@ -84,7 +84,7 @@
 #define ADS1015_REG_CONFIG_CQUE_NONE    (0x0003)  // Disable the comparator and put ALERT/RDY in high state (default)
 */
 
-#define EMON_ADS1115_CHANNELS                  4
+#define EMON_ADS1115_CHANNELS               4
 #define EMON_ADS1115_MAGNITUDES_PER_PORT    2
 
 class EmonADS1115Sensor : public EmonSensor {
@@ -106,13 +106,16 @@ class EmonADS1115Sensor : public EmonSensor {
             // Initialize
             _ads = new ADS1115(_address);
             _ads->initialize();
-            _ads->setMode(ADS1115_MODE_SINGLESHOT);
+            _ads->setMode(ADS1115_MODE_CONTINUOUS);
             _ads->setRate(ADS1115_RATE_860);
             _ads->setGain(ADS1115_PGA_4P096);
-            _ads->setConversionReadyPinMode();
 
             // warmup
-            read(_address);
+            for (unsigned char port=0; port<_ports; port++) {
+                unsigned char channel = getChannel(port);
+                _ads->setMultiplexer(channel + 4);
+                read(channel, _pivot[channel]);
+            }
 
         }
 
@@ -126,8 +129,8 @@ class EmonADS1115Sensor : public EmonSensor {
         // Descriptive name of the slot # index
         String slot(unsigned char index) {
             char buffer[35];
-            unsigned char port = getChannel(index / EMON_ADS1115_MAGNITUDES_PER_PORT);
-            snprintf(buffer, sizeof(buffer), "EMON @ ADS1115 (A%d) @ I2C (0x%02X)", port, _address);
+            unsigned char channel = getChannel(index % _ports);
+            snprintf(buffer, sizeof(buffer), "EMON @ ADS1115 (A%d) @ I2C (0x%02X)", channel, _address);
             return String(buffer);
         }
 
@@ -135,8 +138,7 @@ class EmonADS1115Sensor : public EmonSensor {
         magnitude_t type(unsigned char index) {
             if (index < _count) {
                 _error = SENSOR_ERROR_OK;
-                unsigned char port = getChannel(index / EMON_ADS1115_MAGNITUDES_PER_PORT);
-                unsigned char magnitude = index % EMON_ADS1115_MAGNITUDES_PER_PORT;
+                unsigned char magnitude = index / _ports;
                 if (magnitude == 0) return MAGNITUDE_CURRENT;
                 if (magnitude == 1) return MAGNITUDE_POWER_APPARENT;
                 //if (magnitude == 2) return MAGNITUDE_ENERGY;
@@ -148,9 +150,10 @@ class EmonADS1115Sensor : public EmonSensor {
 
         void pre() {
             //static unsigned long last = 0;
-            for (unsigned char index=0; index<_ports; index++) {
-                unsigned char port = getChannel(index);
-                _current[port] = read(port);
+            for (unsigned char port=0; port<_ports; port++) {
+                unsigned char channel = getChannel(port);
+                _ads->setMultiplexer(channel + 4);
+                _current[port] = read(channel, _pivot[channel]);
                 //if (last > 0) {
                 //    _delta[port] = _current[port] * _voltage * (millis() - last) / 1000;
                 //}
@@ -164,8 +167,8 @@ class EmonADS1115Sensor : public EmonSensor {
 
             if (index < _count) {
                 _error = SENSOR_ERROR_OK;
-                unsigned char port = getChannel(index / EMON_ADS1115_MAGNITUDES_PER_PORT);
-                unsigned char magnitude = index % EMON_ADS1115_MAGNITUDES_PER_PORT;
+                unsigned char port = index % _ports;
+                unsigned char magnitude = index / _ports;
                 if (magnitude == 0) return _current[port];
                 if (magnitude == 1) return _current[port] * _voltage;
                 //if (magnitude == 2) return _energy[port];
@@ -193,11 +196,7 @@ class EmonADS1115Sensor : public EmonSensor {
         }
 
         unsigned int readADC(unsigned char channel) {
-            if (channel < EMON_ADS1115_CHANNELS) {
-                _ads->setMultiplexer(channel + 4);
-                return _ads->getConversion(true);
-            }
-            return 0;
+            return _ads->getConversion();
         }
 
         /*
@@ -272,9 +271,10 @@ class EmonADS1115Sensor : public EmonSensor {
         unsigned char _address;
         unsigned char _mask;
         unsigned char _ports;
-        double _current[EMON_ADS1115_CHANNELS] = {0, 0, 0, 0};
-        //unsigned long _energy[EMON_ADS1115_CHANNELS] = {0, 0, 0, 0};
-        //unsigned long _delta[EMON_ADS1115_CHANNELS] = {0, 0, 0, 0};
+        double _pivot[EMON_ADS1115_CHANNELS] = {0};
+        double _current[EMON_ADS1115_CHANNELS] = {0};
+        //unsigned long _energy[EMON_ADS1115_CHANNELS] = {0};
+        //unsigned long _delta[EMON_ADS1115_CHANNELS] = {0};
 
 
 };

code/espurna/sensors/EmonAnalogSensor.h

@@ -60,7 +60,7 @@ class EmonAnalogSensor : public EmonSensor {
             static unsigned long energy_delta = 0;
 
             if ((last == 0) || (millis() - last > 1000)) {
-                current = read(_gpio);
+                current = read(0, _pivot);
                 energy_delta = current * _voltage * (millis() - last) / 1000;
                 _energy += energy_delta;
                 last = millis();
@@ -79,11 +79,12 @@ class EmonAnalogSensor : public EmonSensor {
     protected:
 
         unsigned int readADC(unsigned char channel) {
-            return analogRead(channel);
+            return analogRead(_gpio);
         }
 
         unsigned char _gpio;
         unsigned long _energy = 0;
+        double _pivot = 0;
 
 
 };

code/espurna/sensors/EmonSensor.h

@@ -18,7 +18,6 @@ class EmonSensor : public BaseSensor {
             // Cache
             _voltage = voltage;
             _adc_counts = 1 << bits;
-            _pivot = _adc_counts >> 1;
 
             // Calculate factor
             _current_factor = ratio * ref / _adc_counts;
@@ -52,7 +51,7 @@ class EmonSensor : public BaseSensor {
             }
         }
 
-        double read(unsigned char channel) {
+        double read(unsigned char channel, double &pivot) {
 
             int sample;
             int max = 0;
@@ -69,8 +68,8 @@ class EmonSensor : public BaseSensor {
                 if (sample < min) min = sample;
 
                 // Digital low pass filter extracts the VDC offset
-                _pivot = (_pivot + (sample - _pivot) / EMON_FILTER_SPEED);
-                filtered = sample - _pivot;
+                pivot = (pivot + (sample - pivot) / EMON_FILTER_SPEED);
+                filtered = sample - pivot;
 
                 // Root-mean-square method
                 sum += (filtered * filtered);
@@ -79,8 +78,8 @@ class EmonSensor : public BaseSensor {
             time_span = millis() - time_span;
 
             // Quick fix
-            if (_pivot < min || max < _pivot) {
-                _pivot = (max + min) / 2.0;
+            if (pivot < min || max < pivot) {
+                pivot = (max + min) / 2.0;
             }
 
             // Calculate current
@@ -95,7 +94,7 @@ class EmonSensor : public BaseSensor {
                 Serial.print("[EMON] Sample frequency (Hz): "); Serial.println(1000 * _samples / time_span);
                 Serial.print("[EMON] Max value: "); Serial.println(max);
                 Serial.print("[EMON] Min value: "); Serial.println(min);
-                Serial.print("[EMON] Midpoint value: "); Serial.println(_pivot);
+                Serial.print("[EMON] Midpoint value: "); Serial.println(pivot);
                 Serial.print("[EMON] RMS value: "); Serial.println(rms);
                 Serial.print("[EMON] Current: "); Serial.println(current);
             #endif
@@ -114,7 +113,6 @@ class EmonSensor : public BaseSensor {
         unsigned long _adc_counts;
         unsigned int _multiplier = 1;
         double _current_factor;
-        double _pivot;
 
         unsigned long _samples = EMON_MAX_SAMPLES;