MAC/WS: Min possible Tack to 1ms and CCA interval to 2ms (ARMmbed#2434)

Author: Jarkko Paso

source/6LoWPAN/ws/ws_common_defines.h

@@ -345,7 +345,7 @@ typedef struct ws_bs_ie {
 // With FHSS we need to check CCA twice on TX channel
 #define WS_NUMBER_OF_CSMA_PERIODS  2
 // Interval between two CCA checks
-#define WS_CSMA_MULTI_CCA_INTERVAL 1000
+#define WS_CSMA_MULTI_CCA_INTERVAL 2000
 
 /* Default FHSS timing information
  *

source/MAC/IEEE802_15_4/mac_mcps_sap.c

@@ -1941,7 +1941,7 @@ int8_t mcps_generic_ack_build(protocol_interface_rf_mac_setup_s *rf_ptr, bool in
 
     tx_buf->ack_len = frame_length;
     uint8_t *mhr_start = ptr;
-    buffer->tx_time = mac_mcps_sap_get_phy_timestamp(rf_ptr) + 300; //Send 300 us later
+    buffer->tx_time = mac_mcps_sap_get_phy_timestamp(rf_ptr) + 1000; // 1ms delay before Ack
 
     ptr = mac_generic_packet_write(rf_ptr, ptr, buffer);