FHSS: Added support for TR51 channel function

Author: Jarkko Paso

source/Service_Libs/fhss/channel_functions.c

@@ -180,3 +180,16 @@ int32_t dh1cf_get_bc_channel_index(uint16_t slot_number, uint16_t bsi, int16_t n
     channel_number = dh1cf_hashword(key, 3, 0) % number_of_channels;
     return channel_number;
 }
+
+int32_t tr51_get_uc_channel_index(uint16_t slot_number, uint8_t *mac, int16_t number_of_channels)
+{
+    uint16_t nearest_prime = tr51_calc_nearest_prime_number(number_of_channels);
+    int32_t channel_table[nearest_prime];
+    int32_t output_table[number_of_channels];
+    uint8_t first_element;
+    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);
+    return output_table[slot_number];
+}

source/Service_Libs/fhss/channel_functions.h

@@ -24,7 +24,7 @@
 void tr51_calculate_channel_table(uint16_t number_of_channels, uint16_t nearest_prime, int32_t *channel_table);
 
 /**
- * @brief Calculate hopping sequence for a specific peer.
+ * @brief Calculate hopping sequence for a specific peer using tr51 channel function.
  * @param channel_table Used channel table.
  * @param channel_table_length Length of the used channel table.
  * @param first_element Start generated by CFD function.
@@ -37,7 +37,16 @@ void tr51_calculate_channel_table(uint16_t number_of_channels, uint16_t nearest_
 uint16_t tr51_calculate_hopping_sequence(int32_t *channel_table, uint16_t channel_table_length, uint8_t first_element, uint8_t step_size, int32_t *output_table, uint16_t *excluded_channels, uint16_t number_of_excluded_channels);
 
 /**
- * @brief Compute the unicast schedule channel index.
+ * @brief Compute the unicast schedule channel index using tr51 channel function.
+ * @param slot_number Current slot number.
+ * @param mac MAC address of the node for which the index is calculated.
+ * @param number_of_channels Number of channels.
+ * @return Channel index.
+ */
+int32_t tr51_get_uc_channel_index(uint16_t slot_number, uint8_t *mac, int16_t number_of_channels);
+
+/**
+ * @brief Compute the unicast schedule channel index using direct hash channel function.
  * @param slot_number Current slot number.
  * @param mac MAC address of the node for which the index is calculated.
  * @param number_of_channels Number of channels.
@@ -46,7 +55,7 @@ uint16_t tr51_calculate_hopping_sequence(int32_t *channel_table, uint16_t channe
 int32_t dh1cf_get_uc_channel_index(uint16_t slot_number, uint8_t *mac, int16_t number_of_channels);
 
 /**
- * @brief Compute the broadcast schedule channel index.
+ * @brief Compute the broadcast schedule channel index using direct hash channel function.
  * @param slot_number Current slot number.
  * @param bsi Broadcast schedule identifier of the node for which the index is calculated.
  * @param number_of_channels Number of channels.

source/Service_Libs/fhss/fhss_ws.c

@@ -50,13 +50,16 @@ static void fhss_ws_update_channel_callback(fhss_structure_t *fhss_structure)
     if (fhss_structure->ws->channel_function == WS_FIXED_CHANNEL) {
 
     } else if (fhss_structure->ws->channel_function == WS_TR51CF) {
-
+        next_channel = fhss_structure->rx_channel = tr51_get_uc_channel_index(fhss_structure->ws->slot, mac_address, fhss_structure->number_of_channels);
+        if (++fhss_structure->ws->slot == fhss_structure->number_of_channels) {
+            fhss_structure->ws->slot = 0;
+        }
     } else if (fhss_structure->ws->channel_function == WS_DH1CF) {
         next_channel = fhss_structure->rx_channel = dh1cf_get_uc_channel_index(fhss_structure->ws->slot, mac_address, fhss_structure->number_of_channels);
+        fhss_structure->ws->slot++;
     } else if (fhss_structure->ws->channel_function == WS_VENDOR_DEF_CF) {
         //TODO: Callback to get channel schedule from application
     }
-    fhss_structure->ws->slot++;
 #ifdef FHSS_CHANNEL_DEBUG
     tr_info("%"PRIu32" UC %u", fhss_structure->platform_functions.fhss_get_timestamp(fhss_structure->fhss_api), next_channel);
 #endif /*FHSS_CHANNEL_DEBUG*/

test/nanostack/unittest/service_libs/channel_functions/channelfunctest.cpp

@@ -63,3 +63,8 @@ TEST(channel_functions, test_tr51_calc_nearest_prime_number)
 {
     CHECK(test_tr51_calc_nearest_prime_number());
 }
+
+TEST(channel_functions, test_tr51_get_uc_channel_index)
+{
+    CHECK(test_tr51_get_uc_channel_index());
+}

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

@@ -162,6 +162,17 @@ bool test_tr51_calculate_hopping_sequence()
     return true;
 }
 
+bool test_tr51_get_uc_channel_index()
+{
+    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]) {
+            return false;
+        }
+    }
+    return true;
+}
+
 bool test_dh1cf_get_uc_channel_index()
 {
     int32_t test_dh1cf_channel_table_1[10] = {19, 128, 3, 53, 79, 24, 68, 118, 7, 51};

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

@@ -30,6 +30,7 @@ bool test_tr51_calculate_hopping_sequence();
 bool test_dh1cf_get_uc_channel_index();
 bool test_dh1cf_get_bc_channel_index();
 bool test_tr51_calc_nearest_prime_number();
+bool test_tr51_get_uc_channel_index();
 
 #ifdef __cplusplus
 }