Remove i2c begin from begin(). This causes the I2C hardware to reset. This may break code.

Other changes: change from boolean to bool typedef for better cross compiler support.

Author: Nathan Seidle

src/SparkFun_SCD30_Arduino_Library.cpp

@@ -33,14 +33,10 @@ SCD30::SCD30(void)
 }
 
 //Initialize the Serial port
-boolean SCD30::begin(TwoWire &wirePort)
+bool SCD30::begin(TwoWire &wirePort)
 {
   _i2cPort = &wirePort; //Grab which port the user wants us to use
 
-  //We expect caller to begin their I2C port, with the speed of their choice external to the library
-  //But if they forget, we start the hardware here.
-  _i2cPort->begin();
-  
   /* Especially during obtaining the ACK BIT after a byte sent the SCD30 is using clock stretching  (but NOT only there)!
    * The need for clock stretching is described in the Sensirion_CO2_Sensors_SCD30_Interface_Description.pdf
    *
@@ -54,17 +50,17 @@ boolean SCD30::begin(TwoWire &wirePort)
    * and now wait for clock stretch to be controlled by the client.
    */
 
-   #if defined(ARDUINO_ARCH_ESP8266)
-   	_i2cPort->setClockStretchLimit(200000);
-   #endif
+#if defined(ARDUINO_ARCH_ESP8266)
+  _i2cPort->setClockStretchLimit(200000);
+#endif
 
   //Check for device to respond correctly
-  if(beginMeasuring() == true) //Start continuous measurements
+  if (beginMeasuring() == true) //Start continuous measurements
   {
-	setMeasurementInterval(2); //2 seconds between measurements
-	setAutoSelfCalibration(true); //Enable auto-self-calibration
-	
-	return (true);
+    setMeasurementInterval(2);    //2 seconds between measurements
+    setAutoSelfCalibration(true); //Enable auto-self-calibration
+
+    return (true);
   }
 
   return (false); //Something went wrong
@@ -75,7 +71,7 @@ boolean SCD30::begin(TwoWire &wirePort)
 uint16_t SCD30::getCO2(void)
 {
   if (co2HasBeenReported == true) //Trigger a new read
-    readMeasurement(); //Pull in new co2, humidity, and temp into global vars
+    readMeasurement();            //Pull in new co2, humidity, and temp into global vars
 
   co2HasBeenReported = true;
 
@@ -87,7 +83,7 @@ uint16_t SCD30::getCO2(void)
 float SCD30::getHumidity(void)
 {
   if (humidityHasBeenReported == true) //Trigger a new read
-    readMeasurement(); //Pull in new co2, humidity, and temp into global vars
+    readMeasurement();                 //Pull in new co2, humidity, and temp into global vars
 
   humidityHasBeenReported = true;
 
@@ -99,15 +95,15 @@ float SCD30::getHumidity(void)
 float SCD30::getTemperature(void)
 {
   if (temperatureHasBeenReported == true) //Trigger a new read
-    readMeasurement(); //Pull in new co2, humidity, and temp into global vars
+    readMeasurement();                    //Pull in new co2, humidity, and temp into global vars
 
   temperatureHasBeenReported = true;
 
   return temperature;
 }
 
 //Enables or disables the ASC
-bool SCD30::setAutoSelfCalibration(boolean enable)
+bool SCD30::setAutoSelfCalibration(bool enable)
 {
   if (enable)
     return sendCommand(COMMAND_AUTOMATIC_SELF_CALIBRATION, 1); //Activate continuous ASC
@@ -119,7 +115,8 @@ bool SCD30::setAutoSelfCalibration(boolean enable)
 //The reference CO2 concentration has to be within the range 400 ppm ≤ cref(CO2) ≤ 2000 ppm.
 bool SCD30::setForcedRecalibrationFactor(uint16_t concentration)
 {
-  if(concentration < 400 || concentration > 2000) {
+  if (concentration < 400 || concentration > 2000)
+  {
     return false; //Error check.
   }
   return sendCommand(COMMAND_SET_FORCED_RECALIBRATION_FACTOR, concentration);
@@ -129,7 +126,7 @@ bool SCD30::setForcedRecalibrationFactor(uint16_t concentration)
 float SCD30::getTemperatureOffset()
 {
   uint16_t response = readRegister(COMMAND_SET_TEMPERATURE_OFFSET);
-  return (float) response / 100;
+  return (float)response / 100;
 }
 
 //Set the temperature offset. See 1.3.8.
@@ -149,7 +146,7 @@ bool SCD30::setAltitudeCompensation(uint16_t altitude)
 //mbar can be 700 to 1200
 bool SCD30::setAmbientPressure(uint16_t pressure_mbar)
 {
-  if(pressure_mbar < 700 || pressure_mbar > 1200) 
+  if (pressure_mbar < 700 || pressure_mbar > 1200)
   {
     return false;
   }
@@ -161,15 +158,15 @@ bool SCD30::setAmbientPressure(uint16_t pressure_mbar)
 //is powered down while continuous measurement mode is active SCD30 will measure
 //continuously after repowering without sending the measurement command.
 //Returns true if successful
-boolean SCD30::beginMeasuring(uint16_t pressureOffset)
+bool SCD30::beginMeasuring(uint16_t pressureOffset)
 {
-  return(sendCommand(COMMAND_CONTINUOUS_MEASUREMENT, pressureOffset));
+  return (sendCommand(COMMAND_CONTINUOUS_MEASUREMENT, pressureOffset));
 }
 
 //Overload - no pressureOffset
-boolean SCD30::beginMeasuring(void)
+bool SCD30::beginMeasuring(void)
 {
-  return(beginMeasuring(0));
+  return (beginMeasuring(0));
 }
 
 //Sets interval between measurements
@@ -180,18 +177,19 @@ bool SCD30::setMeasurementInterval(uint16_t interval)
 }
 
 //Returns true when data is available
-boolean SCD30::dataAvailable()
+bool SCD30::dataAvailable()
 {
   uint16_t response = readRegister(COMMAND_GET_DATA_READY);
 
-  if (response == 1) return (true);
+  if (response == 1)
+    return (true);
   return (false);
 }
 
 //Get 18 bytes from SCD30
 //Updates global variables with floats
 //Returns true if success
-boolean SCD30::readMeasurement()
+bool SCD30::readMeasurement()
 {
   //Verify we have data from the sensor
   if (dataAvailable() == false)
@@ -202,7 +200,7 @@ boolean SCD30::readMeasurement()
   uint32_t tempTemperature = 0;
 
   _i2cPort->beginTransmission(SCD30_ADDRESS);
-  _i2cPort->write(COMMAND_READ_MEASUREMENT >> 8); //MSB
+  _i2cPort->write(COMMAND_READ_MEASUREMENT >> 8);   //MSB
   _i2cPort->write(COMMAND_READ_MEASUREMENT & 0xFF); //LSB
   if (_i2cPort->endTransmission() != 0)
     return (0); //Sensor did not ACK
@@ -212,52 +210,56 @@ boolean SCD30::readMeasurement()
   if (_i2cPort->available())
   {
     byte bytesToCrc[2];
-    for (byte x = 0 ; x < 18 ; x++)
+    for (byte x = 0; x < 18; x++)
     {
       byte incoming = _i2cPort->read();
 
       switch (x)
       {
-        case 0:
-        case 1:
-        case 3:
-        case 4:
-          tempCO2 <<= 8;
-          tempCO2 |= incoming;
-          bytesToCrc[x%3] = incoming;
-          break;
-        case 6:
-        case 7:
-        case 9:
-        case 10:
-          tempTemperature <<= 8;
-          tempTemperature |= incoming;
-          bytesToCrc[x%3] = incoming;
-          break;
-        case 12:
-        case 13:
-        case 15:
-        case 16:
-          tempHumidity <<= 8;
-          tempHumidity |= incoming;
-          bytesToCrc[x%3] = incoming;
-          break;
-        default:
-          //Validate CRC
-          const uint8_t foundCrc = computeCRC8(bytesToCrc, 2);
-          if (foundCrc != incoming) {
-            Serial.printf("Found CRC in byte %u, expected %u, got %u\n", x, incoming, foundCrc);
-            error = true;
-          }
-          break;
+      case 0:
+      case 1:
+      case 3:
+      case 4:
+        tempCO2 <<= 8;
+        tempCO2 |= incoming;
+        bytesToCrc[x % 3] = incoming;
+        break;
+      case 6:
+      case 7:
+      case 9:
+      case 10:
+        tempTemperature <<= 8;
+        tempTemperature |= incoming;
+        bytesToCrc[x % 3] = incoming;
+        break;
+      case 12:
+      case 13:
+      case 15:
+      case 16:
+        tempHumidity <<= 8;
+        tempHumidity |= incoming;
+        bytesToCrc[x % 3] = incoming;
+        break;
+      default:
+        //Validate CRC
+        const uint8_t foundCrc = computeCRC8(bytesToCrc, 2);
+        if (foundCrc != incoming)
+        {
+          Serial.printf("Found CRC in byte %u, expected %u, got %u\n", x, incoming, foundCrc);
+          error = true;
+        }
+        break;
       }
     }
-  } else {
+  }
+  else
+  {
     Serial.printf("No SCD30 data found from I2C, i2c claims we should receive %u bytes\n", receivedBytes);
     return false;
   }
 
-  if (error) {
+  if (error)
+  {
     Serial.println("Encountered error reading SCD30 data.");
     return false;
   }
@@ -278,7 +280,7 @@ boolean SCD30::readMeasurement()
 uint16_t SCD30::readRegister(uint16_t registerAddress)
 {
   _i2cPort->beginTransmission(SCD30_ADDRESS);
-  _i2cPort->write(registerAddress >> 8); //MSB
+  _i2cPort->write(registerAddress >> 8);   //MSB
   _i2cPort->write(registerAddress & 0xFF); //LSB
   if (_i2cPort->endTransmission() != 0)
     return (0); //Sensor did not ACK
@@ -294,17 +296,17 @@ uint16_t SCD30::readRegister(uint16_t registerAddress)
 }
 
 //Sends a command along with arguments and CRC
-boolean SCD30::sendCommand(uint16_t command, uint16_t arguments)
+bool SCD30::sendCommand(uint16_t command, uint16_t arguments)
 {
   uint8_t data[2];
   data[0] = arguments >> 8;
   data[1] = arguments & 0xFF;
   uint8_t crc = computeCRC8(data, 2); //Calc CRC on the arguments only, not the command
 
   _i2cPort->beginTransmission(SCD30_ADDRESS);
-  _i2cPort->write(command >> 8); //MSB
-  _i2cPort->write(command & 0xFF); //LSB
-  _i2cPort->write(arguments >> 8); //MSB
+  _i2cPort->write(command >> 8);     //MSB
+  _i2cPort->write(command & 0xFF);   //LSB
+  _i2cPort->write(arguments >> 8);   //MSB
   _i2cPort->write(arguments & 0xFF); //LSB
   _i2cPort->write(crc);
   if (_i2cPort->endTransmission() != 0)
@@ -314,10 +316,10 @@ boolean SCD30::sendCommand(uint16_t command, uint16_t arguments)
 }
 
 //Sends just a command, no arguments, no CRC
-boolean SCD30::sendCommand(uint16_t command)
+bool SCD30::sendCommand(uint16_t command)
 {
   _i2cPort->beginTransmission(SCD30_ADDRESS);
-  _i2cPort->write(command >> 8); //MSB
+  _i2cPort->write(command >> 8);   //MSB
   _i2cPort->write(command & 0xFF); //LSB
   if (_i2cPort->endTransmission() != 0)
     return (false); //Sensor did not ACK
@@ -334,11 +336,11 @@ uint8_t SCD30::computeCRC8(uint8_t data[], uint8_t len)
 {
   uint8_t crc = 0xFF; //Init with 0xFF
 
-  for (uint8_t x = 0 ; x < len ; x++)
+  for (uint8_t x = 0; x < len; x++)
   {
     crc ^= data[x]; // XOR-in the next input byte
 
-    for (uint8_t i = 0 ; i < 8 ; i++)
+    for (uint8_t i = 0; i < 8; i++)
     {
       if ((crc & 0x80) != 0)
         crc = (uint8_t)((crc << 1) ^ 0x31);

src/SparkFun_SCD30_Arduino_Library.h

@@ -25,10 +25,10 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#pragma once
+#ifndef __SparkFun_SCD30_ARDUINO_LIBARARY_H__
+#define __SparkFun_SCD30_ARDUINO_LIBARARY_H__
 
 #include "Arduino.h"
-
 #include <Wire.h>
 
 //The default I2C address for the SCD30 is 0x61.
@@ -47,13 +47,13 @@
 
 class SCD30
 {
-  public:
-    SCD30(void);
+public:
+	SCD30(void);
 
-    boolean begin(TwoWire &wirePort = Wire); //By default use Wire port
+	bool begin(TwoWire &wirePort = Wire); //By default use Wire port
 
-	boolean beginMeasuring(uint16_t pressureOffset);
-	boolean beginMeasuring(void);
+	bool beginMeasuring(uint16_t pressureOffset);
+	bool beginMeasuring(void);
 
 	uint16_t getCO2(void);
 	float getHumidity(void);
@@ -63,33 +63,33 @@ class SCD30
 	bool setMeasurementInterval(uint16_t interval);
 	bool setAmbientPressure(uint16_t pressure_mbar);
 	bool setAltitudeCompensation(uint16_t altitude);
-	bool setAutoSelfCalibration(boolean enable);
+	bool setAutoSelfCalibration(bool enable);
 	bool setForcedRecalibrationFactor(uint16_t concentration);
 	bool setTemperatureOffset(float tempOffset);
 
-	boolean dataAvailable();
-	boolean readMeasurement();
+	bool dataAvailable();
+	bool readMeasurement();
 
-	boolean sendCommand(uint16_t command, uint16_t arguments);
-	boolean sendCommand(uint16_t command);
+	bool sendCommand(uint16_t command, uint16_t arguments);
+	bool sendCommand(uint16_t command);
 
 	uint16_t readRegister(uint16_t registerAddress);
 
 	uint8_t computeCRC8(uint8_t data[], uint8_t len);
 
-  private:
-    //Variables
-    TwoWire *_i2cPort; //The generic connection to user's chosen I2C hardware
+private:
+	//Variables
+	TwoWire *_i2cPort; //The generic connection to user's chosen I2C hardware
 
 	//Global main datums
 	float co2 = 0;
 	float temperature = 0;
 	float humidity = 0;
-	
+
 	//These track the staleness of the current data
 	//This allows us to avoid calling readMeasurement() every time individual datums are requested
-	boolean co2HasBeenReported = true;
-	boolean humidityHasBeenReported = true;
-	boolean temperatureHasBeenReported = true;
-	
+	bool co2HasBeenReported = true;
+	bool humidityHasBeenReported = true;
+	bool temperatureHasBeenReported = true;
 };
+#endif