MAC: Fixed multi csma

Author: Jarkko Paso

source/MAC/IEEE802_15_4/mac_mcps_sap.c

@@ -1831,7 +1831,7 @@ static int8_t mcps_pd_data_cca_trig(protocol_interface_rf_mac_setup_s *rf_ptr, m
         // Use double CCA check with FHSS for data packets only
         if (rf_ptr->fhss_api && !rf_ptr->mac_ack_tx_active && !rf_ptr->active_pd_data_request->asynch_request) {
             if ((buffer->tx_time - (rf_ptr->multi_cca_interval * (rf_ptr->number_of_csma_ca_periods - 1))) > mac_mcps_sap_get_phy_timestamp(rf_ptr)) {
-                buffer->csma_periods_left = rf_ptr->number_of_csma_ca_periods;
+                buffer->csma_periods_left = rf_ptr->number_of_csma_ca_periods - 1;
                 buffer->tx_time -= (rf_ptr->multi_cca_interval * (rf_ptr->number_of_csma_ca_periods - 1));
             }
         }

source/MAC/IEEE802_15_4/mac_pd_sap.c

@@ -41,7 +41,7 @@
 // Measured 3750us with 1280 byte secured packet from calculating TX time to starting CSMA timer on PHY.
 // Typically varies from 500us to several milliseconds depending on packet size and the platform.
 // MAC should learn and make this dynamic by sending first few packets with predefined CSMA period.
-#define MIN_FHSS_CSMA_PERIOD_US    4000
+#define MIN_FHSS_CSMA_PERIOD_US    5000
 
 static int8_t mac_data_interface_tx_done_cb(protocol_interface_rf_mac_setup_s *rf_ptr, phy_link_tx_status_e status, uint8_t cca_retry, uint8_t tx_retry);
 static void  mac_sap_cca_fail_cb(protocol_interface_rf_mac_setup_s *rf_ptr);
@@ -448,7 +448,8 @@ static int8_t mac_data_interface_tx_done_cb(protocol_interface_rf_mac_setup_s *r
                 mac_tx_done_state_set(rf_ptr, MAC_UNKNOWN_DESTINATION);
                 return PHY_TX_NOT_ALLOWED;
             }
-            if (--active_buf->csma_periods_left > 0) {
+            if (active_buf->csma_periods_left > 0) {
+                active_buf->csma_periods_left--;
                 active_buf->tx_time += rf_ptr->multi_cca_interval;
                 mac_pd_sap_set_phy_tx_time(rf_ptr, active_buf->tx_time, true);
                 return PHY_RESTART_CSMA;