Allow reading status register

Allow reading the status register. This register is important in determining if the value of the ALS and proximity sensor is valid.

Not changing the read funcionts since I assume there was a reason that the status register was not checked (performance?).

Author: tcirstea

src/SparkFun_APDS9960.cpp

@@ -198,6 +198,23 @@ bool SparkFun_APDS9960::init()
  * Public methods for controlling the APDS-9960
  ******************************************************************************/
 
+/**
+ * @brief Reads and returns the contents of the STATUS register
+ *
+ * @return Contents of the STATUS register. 0xFF if error.
+ */
+uint8_t SparkFun_APDS9960::getStatusRegister()
+{
+    uint8_t status_value;
+
+    /* Read current ENABLE register */
+    if(!wireReadDataByte(APDS9960_STATUS, status_value) ) {
+        return ERROR;
+    }
+
+    return status_value;
+}
+
 /**
  * @brief Reads and returns the contents of the ENABLE register
  *

src/SparkFun_APDS9960.h

@@ -98,6 +98,14 @@
 #define APDS9960_GEN            0b01000000
 #define APDS9960_GVALID         0b00000001
 
+/* Status bit fields */
+#define APDS9960_AVALID         0b0000001
+#define APDS9960_PVALID         0b0000010
+#define APDS9960_GINT           0b0000100
+#define APDS9960_AINT           0b0010000
+#define APDS9960_PGSAT          0b0100000
+#define APDS9960_CPSAT          0b1000000
+
 /* On/Off definitions */
 #define OFF                     0
 #define ON                      1