Merge pull request ARMmbed#1552 from ARMmbed/cf_update

FHSS: TR51 channel function updated (bug in the spec?)

Author: Jarkko Paso

source/Service_Libs/fhss/channel_functions.c

@@ -129,9 +129,7 @@ uint16_t tr51_calculate_hopping_sequence(int32_t *channel_table, uint16_t channe
             }
         }
         index += step_size;
-        while (index >= channel_table_length) {
-            index -= channel_table_length;
-        }
+        index %= channel_table_length;
     }
     return slot;
 }
@@ -190,6 +188,8 @@ int32_t tr51_get_uc_channel_index(uint16_t slot_number, uint8_t *mac, int16_t nu
     uint8_t step_size;
     tr51_calculate_channel_table(number_of_channels, nearest_prime, channel_table);
     tr51_compute_cfd(mac, &first_element, &step_size, nearest_prime);
-    tr51_calculate_hopping_sequence(channel_table, number_of_channels, first_element, step_size, output_table, NULL, 0);
+// Not sure yet which one is the correct second parameter
+//    tr51_calculate_hopping_sequence(channel_table, number_of_channels, first_element, step_size, output_table, NULL, 0);
+    tr51_calculate_hopping_sequence(channel_table, nearest_prime, first_element, step_size, output_table, NULL, 0);
     return output_table[slot_number];
 }

test/nanostack/unittest/service_libs/channel_functions/test_channel_functions.c

@@ -53,6 +53,23 @@ const int32_t test_HopSequenceTable[129] =  {   4,93,31,84,55,3,116,123,
                                                 49,110,44,97,29,43,79,67,
                                                 77,48,100,51,14,21,94,23,
                                                 22 };
+const int32_t test_HopSequenceTable2[129] =  {   4, 42, 85, 0, 32, 116, 19, 17,
+                                                119, 44, 25, 71, 95, 37, 75, 48,
+                                                125, 106, 92, 39, 23, 78, 56, 10,
+                                                127, 27, 3, 87, 76, 5, 110, 28,
+                                                57, 61, 70, 101, 77, 112, 13, 40,
+                                                58, 94, 128, 15, 34, 121, 55, 114,
+                                                60, 83, 49, 105, 104, 2, 9, 67,
+                                                20, 99, 12, 24, 21, 89, 16, 8,
+                                                63, 115, 84, 64, 36, 107, 111, 68,
+                                                53, 98, 113, 108, 79, 122, 45, 96,
+                                                126, 14, 69, 6, 102, 120, 50, 31,
+                                                30, 91, 72, 38, 41, 47, 117, 86,
+                                                82, 43, 66, 81, 7, 103, 51, 11,
+                                                46, 74, 90, 52, 93, 124, 109, 73,
+                                                88, 123, 65, 62, 1, 97, 29, 33,
+                                                18, 59, 35, 100, 118, 54, 80, 26,
+                                                22 };
 
 const uint16_t prime_number_table[] = { 2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
                                         31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
@@ -141,8 +158,8 @@ bool test_tr51_calculate_hopping_sequence()
     int32_t outtable[129];
     tr51_calculate_channel_table(129, 131, chantable);
     // Test generating hopping sequence table of specific peer
-    tr51_calculate_hopping_sequence(chantable, 129, 122, 119, outtable, NULL, 0);
-    if (memcmp(outtable, test_HopSequenceTable, 129*4)) {
+    tr51_calculate_hopping_sequence(chantable, 131, 122, 119, outtable, NULL, 0);
+    if (memcmp(outtable, test_HopSequenceTable2, 129*4)) {
         return false;
     }
     // Test that every channel exists once and only once.
@@ -164,11 +181,30 @@ bool test_tr51_calculate_hopping_sequence()
 
 bool test_tr51_get_uc_channel_index()
 {
+    uint16_t number_of_channels = 129;
+    int32_t channel;
+    int32_t test_table[number_of_channels];
     uint8_t mac[8] = {0x00, 0x13, 0x50, 0x04, 0x00, 0x00, 0x05, 0xf8};
-    for (int i=0; i<129; i++) {
-        if (tr51_get_uc_channel_index(i, mac, 129) != test_HopSequenceTable[i]) {
+    for (int i=0; i<number_of_channels; i++) {
+        test_table[i] = channel = tr51_get_uc_channel_index(i, mac, number_of_channels);
+// Not sure yet which one is correct since there might be bug in spec
+//        if (channel != test_HopSequenceTable[i]) {
+        if (channel != test_HopSequenceTable2[i]) {
+            return false;
+        }
+    }
+    // Test that every channel exists once and only once.
+    int k=0;
+    for (int h=0; h<number_of_channels; h++) {
+        for (int j=0; j<number_of_channels; j++) {
+            if (test_table[j] == h) {
+                k++;
+            }
+        }
+        if (k != 1) {
             return false;
         }
+        k=0;
     }
     return true;
 }