Error reset on _pre for different sensors

code/espurna/sensors/BMX280Sensor.h

@@ -89,6 +89,7 @@ class BMX280Sensor : public I2CSensor {
                 _error = SENSOR_ERROR_UNKNOWN_ID;
                 return;
             }
+            _error = SENSOR_ERROR_OK;
 
             #if BMX280_MODE == 1
                 forceRead();

code/espurna/sensors/DHTSensor.h

@@ -80,6 +80,7 @@ class DHTSensor : public BaseSensor {
 
         // Pre-read hook (usually to populate registers with up-to-date data)
         void pre() {
+            _error = SENSOR_ERROR_OK;
             _read();
         }
 

code/espurna/sensors/DallasSensor.h

@@ -209,6 +209,11 @@ class DallasSensor : public BaseSensor {
             return MAGNITUDE_NONE;
         }
 
+        // Pre-read hook (usually to populate registers with up-to-date data)
+        void pre() {
+            _error = SENSOR_ERROR_OK;
+        }
+
         // Current value for slot # index
         double value(unsigned char index) {
 

code/espurna/sensors/EmonADC121Sensor.h

@@ -112,6 +112,8 @@ class EmonADC121Sensor : public EmonSensor {
                 last = millis();
             #endif
 
+            _error = SENSOR_ERROR_OK;
+
         }
 
         // Type for slot # index

code/espurna/sensors/EmonADS1X15Sensor.h

@@ -241,6 +241,7 @@ class EmonADS1X15Sensor : public EmonSensor {
                 #endif
             }
             last = millis();
+            _error = SENSOR_ERROR_OK;
         }
 
         // Current value for slot # index

code/espurna/sensors/EmonAnalogSensor.h

@@ -94,6 +94,8 @@ class EmonAnalogSensor : public EmonSensor {
                 last = millis();
             #endif
 
+            _error = SENSOR_ERROR_OK;
+
         }
 
         // Current value for slot # index

code/espurna/sensors/MHZ19Sensor.h

@@ -197,6 +197,8 @@ class MHZ19Sensor : public BaseSensor {
                     _error = SENSOR_ERROR_OUT_OF_RANGE;
                 }
 
+            } else {
+                _error = SENSOR_ERROR_CRC;
             }
 
         }

code/espurna/sensors/SHT3XI2CSensor.h

@@ -66,6 +66,8 @@ class SHT3XI2CSensor : public I2CSensor {
         // Pre-read hook (usually to populate registers with up-to-date data)
         void pre() {
 
+            _error = SENSOR_ERROR_OK;
+            
             unsigned char buffer[6];
 
             #if I2C_USE_BRZO

code/espurna/sensors/SI7021Sensor.h

@@ -93,9 +93,9 @@ class SI7021Sensor : public I2CSensor {
 
             _error = SENSOR_ERROR_UNKNOWN_ID;
             if (_chip == 0) return;
+            _error = SENSOR_ERROR_OK;
 
             double value;
-            _error = SENSOR_ERROR_OK;
 
             value = _read(SI7021_CMD_TMP_NOHOLD);
             if (_error != SENSOR_ERROR_OK) return;