fix comment issues, move to using toolkit functions for swaping - not hard coded bit fiddling

Author: gigapod

src/sfeTkArdI2C.cpp

@@ -209,7 +209,7 @@ sfeTkError_t sfeTkArdI2C::writeRegisterRegion(uint8_t devReg, const uint8_t *dat
 //
 sfeTkError_t sfeTkArdI2C::writeRegister16Region(uint16_t devReg, const uint8_t *data, size_t length)
 {
-    // devReg = ((devReg << 8) & 0xff00) | ((devReg >> 8) & 0x00ff);
+    // Byteorder check
     if (sftk_system_byteorder() != _byteOrder)
         devReg = sftk_byte_swap(devReg);
     return writeRegisterRegionAddress((uint8_t *)&devReg, 2, data, length);
@@ -230,7 +230,7 @@ sfeTkError_t sfeTkArdI2C::writeRegister16Region16(uint16_t devReg, const uint16_
 
     // okay, we need to swap
     devReg = sftk_byte_swap(devReg);
-    // devReg = ((devReg << 8) & 0xff00) | ((devReg >> 8) & 0x00ff);
+    
     uint16_t data16[length];
     for (size_t i = 0; i < length; i++)
         data16[i] = ((data[i] << 8) & 0xff00) | ((data[i] >> 8) & 0x00ff);
@@ -393,15 +393,16 @@ sfeTkError_t sfeTkArdI2C::readRegister16Region16(uint16_t devReg, uint16_t *data
 {
     // if the system byte order is the same as the desired order, flip the address
     if (sftk_system_byteorder() != _byteOrder)
-        devReg = ((devReg << 8) & 0xff00) | ((devReg >> 8) & 0x00ff);
+        devReg = sftk_byte_swap(devReg);
+        
 
     sfeTkError_t status = readRegisterRegionAnyAddress((uint8_t *)&devReg, 2, (uint8_t *)data, numBytes * 2, readWords);
 
     // Do we need to flip the byte order?
     if (status == kSTkErrOk && sftk_system_byteorder() != _byteOrder)
     {
         for (size_t i = 0; i < numBytes; i++)
-            data[i] = ((data[i] << 8) & 0xff00) | ((data[i] >> 8) & 0x00ff);
+            data[i] = sftk_byte_swap(data[i]);
     }
     readWords = readWords / 2; // convert to words
     return status;