diff --git a/tests/xua_unit_tests/src/test_hid.c b/tests/xua_unit_tests/src/test_hid.c
index aadf02f9..05c015fa 100644
--- a/tests/xua_unit_tests/src/test_hid.c
+++ b/tests/xua_unit_tests/src/test_hid.c
@@ -6,6 +6,19 @@
 #include "xua_unit_tests.h"
 #include "xua_hid_report_descriptor.h"
 
+#define HID_REPORT_ITEM_TYPE_GLOBAL     ( 0x01 )
+#define HID_REPORT_ITEM_TYPE_LOCAL      ( 0x02 )
+#define HID_REPORT_ITEM_TYPE_MAIN       ( 0x00 )
+#define HID_REPORT_ITEM_TYPE_RESERVED   ( 0x03 )
+
+#define MAX_VALID_BIT   ( 7 )
+#define MAX_VALID_BYTE  ( 2 )
+
+#define MIN_VALID_BIT   ( 0 )
+#define MIN_VALID_BYTE  ( 0 )
+
+#define SPACEBAR_KEY_CODE   ( 0x2C )
+
 static unsigned construct_usage_header( unsigned size )
 {
     unsigned header = 0x00;
@@ -35,9 +48,9 @@ void test_prepared_hidGetReportDescriptor( void )
 // Configurable and non-configurable item tests
 void test_configurable_item_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char data[ 1 ] = { 0x2C };   // Spacebar keycode
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char data[ 1 ] = { SPACEBAR_KEY_CODE };
     const unsigned char header = construct_usage_header( sizeof data / sizeof( unsigned char ));
 
     unsigned retVal = hidSetReportItem( byte, bit, header, data );
@@ -46,9 +59,9 @@ void test_configurable_item_hidSetReportItem( void )
 
 void test_nonconfigurable_item_hidSetReportItem( void )
 {
-    const unsigned bit = 7; // Reserved bit
-    const unsigned byte = 0;
-    const unsigned char data[ 1 ] = { 0x2C };   // Spacebar keycode
+    const unsigned bit = 7;     // This bit and byte combination should not appear in the
+    const unsigned byte = 0;    // hidConfigurableItems list in hid_report_descriptors.c.
+    const unsigned char data[ 1 ] = { SPACEBAR_KEY_CODE };
     const unsigned char header = construct_usage_header( sizeof data / sizeof( unsigned char ));
 
     unsigned retVal = hidSetReportItem( byte, bit, header, data );
@@ -58,8 +71,8 @@ void test_nonconfigurable_item_hidSetReportItem( void )
 // Bit range tests
 void test_max_bit_hidSetReportItem( void )
 {
-    const unsigned bit = 7;
-    const unsigned byte = 1;    // Only byte 1 has bit 7 not reserved
+    const unsigned bit = MAX_VALID_BIT; // Only byte 1 has bit 7 not reserved,  See the
+    const unsigned byte = 1;            // hidConfigurableItems list in hid_report_descriptors.c.
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -68,8 +81,8 @@ void test_max_bit_hidSetReportItem( void )
 
 void test_min_bit_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -78,8 +91,8 @@ void test_min_bit_hidSetReportItem( void )
 
 void test_overflow_bit_hidSetReportItem( void )
 {
-    const unsigned bit = 8;
-    const unsigned byte = 0;
+    const unsigned bit = MAX_VALID_BIT + 1;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -88,8 +101,8 @@ void test_overflow_bit_hidSetReportItem( void )
 
 void test_underflow_bit_hidSetReportItem( void )
 {
-    const int bit = -1;
-    const unsigned byte = 0;
+    const int bit = MIN_VALID_BIT - 1;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( byte, ( unsigned ) bit, header, NULL );
@@ -99,8 +112,8 @@ void test_underflow_bit_hidSetReportItem( void )
 // Byte range tests
 void test_max_byte_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 2;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MAX_VALID_BYTE;
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -109,8 +122,8 @@ void test_max_byte_hidSetReportItem( void )
 
 void test_min_byte_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -119,8 +132,8 @@ void test_min_byte_hidSetReportItem( void )
 
 void test_overflow_byte_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 4;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MAX_VALID_BYTE + 1;
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -129,8 +142,8 @@ void test_overflow_byte_hidSetReportItem( void )
 
 void test_underflow_byte_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const int byte = -1;
+    const unsigned bit = MIN_VALID_BIT;
+    const int byte = MIN_VALID_BYTE - 1;
     const unsigned char header = construct_usage_header( 0 );
 
     unsigned retVal = hidSetReportItem( ( unsigned ) byte, bit, header, NULL );
@@ -140,8 +153,8 @@ void test_underflow_byte_hidSetReportItem( void )
 // Size range tests
 void test_max_size_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char data[ HID_REPORT_ITEM_MAX_SIZE ] = { 0x00 };
     const unsigned char header = construct_usage_header( HID_REPORT_ITEM_MAX_SIZE );
 
@@ -151,8 +164,8 @@ void test_max_size_hidSetReportItem( void )
 
 void test_min_size_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char header = construct_usage_header( 0x00 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -161,8 +174,8 @@ void test_min_size_hidSetReportItem( void )
 
 void test_unsupported_size_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char header = construct_usage_header( 0x03 );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
@@ -172,8 +185,8 @@ void test_unsupported_size_hidSetReportItem( void )
 // Header tag and type tests
 void test_bad_tag_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
     const unsigned char good_header = construct_usage_header( 0x00 );
 
     for( unsigned tag = 0x01; tag <= 0x0F; ++tag ) {
@@ -183,37 +196,34 @@ void test_bad_tag_hidSetReportItem( void )
     }
 }
 
-void test_local_type_hidSetReportItem( void )
-{
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char header = ( construct_usage_header( 0x00 ) &
-                                 ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
-                                 (( 0x02 << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
-
-    unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
-    TEST_ASSERT_EQUAL_UINT( HID_STATUS_GOOD, retVal );
-}
-
 void test_global_type_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char header = ( construct_usage_header( 0x00 ) &
-                                 ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
-                                 (( 0x01 << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char header = ( construct_usage_header( 0x00 ) & ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
+        (( HID_REPORT_ITEM_TYPE_GLOBAL << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
     TEST_ASSERT_EQUAL_UINT( HID_STATUS_BAD_HEADER, retVal );
 }
 
+void test_local_type_hidSetReportItem( void )
+{
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char header = ( construct_usage_header( 0x00 ) & ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
+        (( HID_REPORT_ITEM_TYPE_LOCAL << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
+
+    unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
+    TEST_ASSERT_EQUAL_UINT( HID_STATUS_GOOD, retVal );
+}
+
 void test_main_type_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char header = ( construct_usage_header( 0x00 ) &
-                                 ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
-                                 (( 0x00 << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char header = ( construct_usage_header( 0x00 ) & ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
+        (( HID_REPORT_ITEM_TYPE_MAIN << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
     TEST_ASSERT_EQUAL_UINT( HID_STATUS_BAD_HEADER, retVal );
@@ -221,11 +231,10 @@ void test_main_type_hidSetReportItem( void )
 
 void test_reserved_type_hidSetReportItem( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char header = ( construct_usage_header( 0x00 ) &
-                                 ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
-                                 (( 0x03 << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char header = ( construct_usage_header( 0x00 ) & ~HID_REPORT_ITEM_HDR_TYPE_MASK ) |
+        (( HID_REPORT_ITEM_TYPE_RESERVED << HID_REPORT_ITEM_HDR_TYPE_SHIFT ) & HID_REPORT_ITEM_HDR_TYPE_MASK );
 
     unsigned retVal = hidSetReportItem( byte, bit, header, NULL );
     TEST_ASSERT_EQUAL_UINT( HID_STATUS_BAD_HEADER, retVal );
@@ -234,9 +243,9 @@ void test_reserved_type_hidSetReportItem( void )
 // Combined function tests
 void test_initial_modification_without_subsequent_preparation( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char data[ 1 ] = { 0x2C };   // Spacebar keycode
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char data[ 1 ] = { SPACEBAR_KEY_CODE };
     const unsigned char header = construct_usage_header( sizeof data / sizeof( unsigned char ));
 
     unsigned retVal = hidSetReportItem( byte, bit, header, data );
@@ -248,9 +257,9 @@ void test_initial_modification_without_subsequent_preparation( void )
 
 void test_initial_modification_with_subsequent_preparation( void )
 {
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char data[ 1 ] = { 0x2C };   // Spacebar keycode
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char data[ 1 ] = { SPACEBAR_KEY_CODE };
     const unsigned char header = construct_usage_header( sizeof data / sizeof( unsigned char ));
 
     unsigned retVal = hidSetReportItem( byte, bit, header, data );
@@ -267,9 +276,9 @@ void test_modification_without_subsequent_preparation( void )
     unsigned char* reportDescPtr = hidGetReportDescriptor();
     TEST_ASSERT_NOT_NULL( reportDescPtr );
 
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char data[ 1 ] = { 0x2C };   // Spacebar keycode
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char data[ 1 ] = { SPACEBAR_KEY_CODE };
     const unsigned char header = construct_usage_header( sizeof data / sizeof( unsigned char ));
 
     unsigned retVal = hidSetReportItem( byte, bit, header, data );
@@ -285,9 +294,9 @@ void test_modification_with_subsequent_preparation( void )
     unsigned char* reportDescPtr = hidGetReportDescriptor();
     TEST_ASSERT_NOT_NULL( reportDescPtr );
 
-    const unsigned bit = 0;
-    const unsigned byte = 0;
-    const unsigned char data[ 1 ] = { 0x2C };   // Spacebar keycode
+    const unsigned bit = MIN_VALID_BIT;
+    const unsigned byte = MIN_VALID_BYTE;
+    const unsigned char data[ 1 ] = { SPACEBAR_KEY_CODE };
     const unsigned char header = construct_usage_header( sizeof data / sizeof( unsigned char ));
 
     unsigned retVal = hidSetReportItem( byte, bit, header, data );