Code review updates

Change constants to Hungarian notation
Move _theBus initializer into header
Change changeAddress() to take a `const uint8_t&`
Remove under read check, since that will be caught by previous check of err
Add address getter

Author: sfe-SparkFro

examples/Example1_BasicReadings/Example1_BasicReadings.ino

@@ -1,13 +1,13 @@
 #include "SparkFun_Qwiic_Ultrasonic_Arduino_Library.h"
 
-// Create an Ultrasonic sensor object
+// Create an ultrasonic sensor object
 QwiicUltrasonic myUltrasonic;
 
 // Here we set the device address. Note that an older version of the Qwiic
 // Ultrasonic firmware used a default address of 0x00. If yours uses 0x00,
 // you'll need to change the address below. It is also recommended to run
 // Example 2 to change the address to the new default.
-uint8_t deviceAddress = QWIIC_ULTRASONIC_DEFAULT_ADDRESS;
+uint8_t deviceAddress = kQwiicUltrasonicDefaultAddress; // 0x2F
 // uint8_t deviceAddress = 0x00;
 
 void setup()
@@ -19,7 +19,7 @@ void setup()
     Wire.begin();
 
     // Attempt to begin the sensor
-    while(myUltrasonic.begin(deviceAddress) == false)
+    while (myUltrasonic.begin(deviceAddress) == false)
     {
         Serial.println("Ultrasonic sensor not connected, check your wiring and I2C address!");
         delay(1000);

examples/Example2_ChangeAddress/Example2_ChangeAddress.ino

@@ -1,14 +1,14 @@
 #include "SparkFun_Qwiic_Ultrasonic_Arduino_Library.h"
 
-// Create an Ultrasonic sensor object
+// Create an ultrasonic sensor object
 QwiicUltrasonic myUltrasonic;
 
 // Here we set the device address. Note that an older version of the Qwiic
 // Ultrasonic firmware used a default address of 0x00. If yours uses 0x00,
 // you'll need to change the address below. It is also recommended to run
 // Example 2 to change the address to the new default.
-uint8_t deviceAddress = QWIIC_ULTRASONIC_DEFAULT_ADDRESS;
-// uint8_t deviceAddress = 0x20;
+uint8_t deviceAddress = kQwiicUltrasonicDefaultAddress; // 0x2F
+// uint8_t deviceAddress = 0x00;
 
 void setup()
 {
@@ -55,7 +55,7 @@ void setup()
         Serial.println(newAddress, HEX);
 
         // Check if the address is valid
-        if (newAddress < QWIIC_ULTRASONIC_MIN_ADDRESS || newAddress > QWIIC_ULTRASONIC_MAX_ADDRESS)
+        if (newAddress < kQwiicUltrasonicMinAddress || newAddress > kQwiicUltrasonicMaxAddress)
         {
             Serial.println("Invalid address!");
             continue;

src/SparkFun_Qwiic_Ultrasonic_Arduino_Library.h

@@ -11,7 +11,7 @@ class QwiicUltrasonic : public sfeQwiicUltrasonic
     /// @param address I2C device address to use for the sensor
     /// @param wirePort Wire port to use for I2C communication
     /// @return True if successful, false otherwise
-    bool begin(uint8_t address = QWIIC_ULTRASONIC_DEFAULT_ADDRESS, TwoWire &wirePort = Wire)
+    bool begin(uint8_t address = kQwiicUltrasonicDefaultAddress, TwoWire &wirePort = Wire)
     {
         // Setup Arudino I2C bus
         _theI2CBus.init(wirePort, address);

src/sfeQwiicUltrasonic.cpp

@@ -1,18 +1,13 @@
 #include "sfeQwiicUltrasonic.h"
 
-sfeQwiicUltrasonic::sfeQwiicUltrasonic()
-{
-    _theBus = nullptr;
-}
-
 sfeTkError_t sfeQwiicUltrasonic::begin(sfeTkII2C *theBus)
 {
     // Nullptr check
     if (theBus == nullptr)
         return kSTkErrFail;
 
     // Check the device address
-    if (theBus->address() < QWIIC_ULTRASONIC_MIN_ADDRESS || theBus->address() > QWIIC_ULTRASONIC_MAX_ADDRESS)
+    if (theBus->address() < kQwiicUltrasonicMinAddress || theBus->address() > kQwiicUltrasonicMaxAddress)
     {
         // An older version of the firmware used 0x00 as the default address.
         // It's not really a valid address, but we need to allow it. Any other
@@ -40,34 +35,27 @@ sfeTkError_t sfeQwiicUltrasonic::triggerAndRead(uint16_t &distance)
     uint8_t rawData[2] = {0, 0};
 
     // Attempt to read the distance
-    sfeTkError_t err = _theBus->readRegisterRegion(QWIIC_ULTRASONIC_REGISTER_TRIGGER, rawData, 2, bytesRead);
+    sfeTkError_t err = _theBus->readRegisterRegion(kQwiicUltrasonicRegisterTrigger, rawData, 2, bytesRead);
 
     // Check whether the read was successful
     if (err)
         return err;
 
-    // Check whether all data was read
-    if (bytesRead != 2)
-        return kSTkErrFail;
-
     // Store raw data
     distance = (rawData[0] << 8) | rawData[1];
 
     // Done!
     return kSTkErrOk;
 }
 
-sfeTkError_t sfeQwiicUltrasonic::changeAddress(uint8_t address)
+sfeTkError_t sfeQwiicUltrasonic::changeAddress(const uint8_t &address)
 {
     // Check whether the address is valid
-    if (address < QWIIC_ULTRASONIC_MIN_ADDRESS || address > QWIIC_ULTRASONIC_MAX_ADDRESS)
+    if (address < kQwiicUltrasonicMinAddress || address > kQwiicUltrasonicMaxAddress)
         return kSTkErrFail;
 
-    // The first bit of the address must be set to 1
-    address |= 0x80;
-
-    // Write the new address to the device
-    sfeTkError_t err = _theBus->writeByte(address);
+    // Write the new address to the device. The first bit must be set to 1
+    sfeTkError_t err = _theBus->writeByte(address | 0x80);
 
     // Check whether the write was successful
     if (err)
@@ -79,3 +67,8 @@ sfeTkError_t sfeQwiicUltrasonic::changeAddress(uint8_t address)
     // Done!
     return kSTkErrOk;
 }
+
+uint8_t sfeQwiicUltrasonic::getAddress()
+{
+    return _theBus->address();
+}

src/sfeQwiicUltrasonic.h

@@ -4,21 +4,23 @@
 #include <stdint.h>
 
 // Available I2C addresses of the Qwiic Ultrasonic
-const uint8_t QWIIC_ULTRASONIC_ADDRESSES[] = {0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
-                                              0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F};
-const uint8_t QWIIC_ULTRASONIC_NUM_ADDRESSES = sizeof(QWIIC_ULTRASONIC_ADDRESSES);
-const uint8_t QWIIC_ULTRASONIC_MIN_ADDRESS = QWIIC_ULTRASONIC_ADDRESSES[0];
-const uint8_t QWIIC_ULTRASONIC_MAX_ADDRESS = QWIIC_ULTRASONIC_ADDRESSES[15];
-const uint8_t QWIIC_ULTRASONIC_DEFAULT_ADDRESS = 0x2F;
+const uint8_t kQwiicUltrasonicAddresses[] = {0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
+                                             0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F};
+const uint8_t kQwiicUltrasonicNumAddresses = sizeof(kQwiicUltrasonicAddresses);
+const uint8_t kQwiicUltrasonicMinAddress = kQwiicUltrasonicAddresses[0];
+const uint8_t kQwiicUltrasonicMaxAddress = kQwiicUltrasonicAddresses[15];
+const uint8_t kQwiicUltrasonicDefaultAddress = 0x2F;
 
 // Register to trigger a new measuremnt and read the previous one
-const uint8_t QWIIC_ULTRASONIC_REGISTER_TRIGGER = 0x01;
+const uint8_t kQwiicUltrasonicRegisterTrigger = 0x01;
 
 class sfeQwiicUltrasonic
 {
   public:
     /// @brief Default constructor
-    sfeQwiicUltrasonic();
+    sfeQwiicUltrasonic() : _theBus(nullptr)
+    {
+    }
 
     /// @brief Begins the Qwiic Ultrasonic sensor
     /// @param theBus I2C bus to use for communication
@@ -37,7 +39,11 @@ class sfeQwiicUltrasonic
     /// @brief Changes the I2C address of the Qwiic Ultrasonic sensor
     /// @param address New address, must be in the range 0x20 to 0x2F
     /// @return 0 for succuss, negative for errors, positive for warnings
-    sfeTkError_t changeAddress(uint8_t address);
+    sfeTkError_t changeAddress(const uint8_t &address);
+
+    /// @brief Gets the current I2C address of the Qwiic Ultrasonic sensor
+    /// @return The current I2C address, 7-bit unshifted
+    uint8_t getAddress();
 
   protected:
     sfeTkII2C *_theBus;