v1.0.20 Add useStaleData

Author: PaulZC

keywords.txt

@@ -49,6 +49,8 @@ sendCommand	KEYWORD2
 readRegister	KEYWORD2
 computeCRC8	KEYWORD2
 
+useStaleData	KEYWORD2
+
 #######################################
 # Constants (LITERAL1)
 #######################################

library.properties

@@ -1,5 +1,5 @@
 name=SparkFun SCD30 Arduino Library
-version=1.0.19
+version=1.0.20
 author=SparkFun Electronics
 maintainer=SparkFun Electronics <sparkfun.com>
 sentence=Library for the Sensirion SCD30 CO2 Sensor

src/SparkFun_SCD30_Arduino_Library.cpp

@@ -107,7 +107,8 @@ uint16_t SCD30::getCO2(void)
   if (co2HasBeenReported == true) // Trigger a new read
   {
     if (readMeasurement() == false) // Pull in new co2, humidity, and temp into global vars
-      co2 = 0;                      // Failed to read sensor
+      if (!_useStaleData)
+        co2 = 0; // Failed to read sensor
   }
 
   co2HasBeenReported = true;
@@ -121,7 +122,8 @@ float SCD30::getHumidity(void)
 {
   if (humidityHasBeenReported == true) // Trigger a new read
     if (readMeasurement() == false)    // Pull in new co2, humidity, and temp into global vars
-      humidity = 0;                    // Failed to read sensor
+      if (!_useStaleData)
+        humidity = 0; // Failed to read sensor
 
   humidityHasBeenReported = true;
 
@@ -134,7 +136,8 @@ float SCD30::getTemperature(void)
 {
   if (temperatureHasBeenReported == true) // Trigger a new read
     if (readMeasurement() == false)       // Pull in new co2, humidity, and temp into global vars
-      temperature = 0;                    // Failed to read sensor
+      if (!_useStaleData)
+        temperature = 0; // Failed to read sensor
 
   temperatureHasBeenReported = true;
 

src/SparkFun_SCD30_Arduino_Library.h

@@ -120,6 +120,8 @@ class SCD30
 
 	uint8_t computeCRC8(uint8_t data[], uint8_t len);
 
+	void useStaleData(bool enable) { _useStaleData = enable; }
+
 private:
 	// Variables
 #ifdef USE_TEENSY3_I2C_LIB
@@ -131,6 +133,7 @@ class SCD30
 	float co2 = 0;
 	float temperature = 0;
 	float humidity = 0;
+	bool _useStaleData = false; // If true, stale data is returned instead of zeros
 
 	// These track the staleness of the current data
 	// This allows us to avoid calling readMeasurement() every time individual datums are requested