diff --git a/os/net/mac/tsch/tsch-conf.h b/os/net/mac/tsch/tsch-conf.h
index c1611e200..76e463a0c 100644
--- a/os/net/mac/tsch/tsch-conf.h
+++ b/os/net/mac/tsch/tsch-conf.h
@@ -365,18 +365,21 @@
 /******** Configuration: CSMA *******/
 
 /* TSCH CSMA-CA parameters, see IEEE 802.15.4e-2012 */
+
 /* Min backoff exponent */
 #ifdef TSCH_CONF_MAC_MIN_BE
 #define TSCH_MAC_MIN_BE TSCH_CONF_MAC_MIN_BE
 #else
 #define TSCH_MAC_MIN_BE 1
 #endif
+
 /* Max backoff exponent */
 #ifdef TSCH_CONF_MAC_MAX_BE
 #define TSCH_MAC_MAX_BE TSCH_CONF_MAC_MAX_BE
 #else
 #define TSCH_MAC_MAX_BE 5
 #endif
+
 /* Max number of re-transmissions */
 #ifdef TSCH_CONF_MAC_MAX_FRAME_RETRIES
 #define TSCH_MAC_MAX_FRAME_RETRIES TSCH_CONF_MAC_MAX_FRAME_RETRIES
@@ -391,6 +394,13 @@
 #define TSCH_PACKET_EACK_WITH_SRC_ADDR 0
 #endif
 
+/* Perform CCA before sending? */
+#ifdef TSCH_CONF_CCA_ENABLED
+#define TSCH_CCA_ENABLED TSCH_CONF_CCA_ENABLED
+#else
+#define TSCH_CCA_ENABLED 0
+#endif
+
 /* Include destination address in ACK? */
 #ifdef TSCH_PACKET_CONF_EACK_WITH_DEST_ADDR
 #define TSCH_PACKET_EACK_WITH_DEST_ADDR TSCH_PACKET_CONF_EACK_WITH_DEST_ADDR
diff --git a/os/net/mac/tsch/tsch-slot-operation.c b/os/net/mac/tsch/tsch-slot-operation.c
index 5c7dc904d..b1a3f6ba8 100644
--- a/os/net/mac/tsch/tsch-slot-operation.c
+++ b/os/net/mac/tsch/tsch-slot-operation.c
@@ -464,9 +464,9 @@ PT_THREAD(tsch_tx_slot(struct pt *pt, struct rtimer *t))
       /* Did we set the frame pending bit to request an extra burst link? */
       static int burst_link_requested;
 
-#if CCA_ENABLED
+#if TSCH_CCA_ENABLED
       static uint8_t cca_status;
-#endif
+#endif /* TSCH_CCA_ENABLED */
 
       /* get payload */
       packet = queuebuf_dataptr(current_packet->qb);
@@ -507,22 +507,22 @@ PT_THREAD(tsch_tx_slot(struct pt *pt, struct rtimer *t))
       if(packet_ready && NETSTACK_RADIO.prepare(packet, packet_len) == 0) { /* 0 means success */
         static rtimer_clock_t tx_duration;
 
-#if CCA_ENABLED
+#if TSCH_CCA_ENABLED
         cca_status = 1;
         /* delay before CCA */
-        TSCH_SCHEDULE_AND_YIELD(pt, t, current_slot_start, TS_CCA_OFFSET, "cca");
+        TSCH_SCHEDULE_AND_YIELD(pt, t, current_slot_start, tsch_timing[tsch_ts_cca_offset], "cca");
         TSCH_DEBUG_TX_EVENT();
         tsch_radio_on(TSCH_RADIO_CMD_ON_WITHIN_TIMESLOT);
         /* CCA */
-        BUSYWAIT_UNTIL_ABS(!(cca_status |= NETSTACK_RADIO.channel_clear()),
-                           current_slot_start, TS_CCA_OFFSET + TS_CCA);
+        BUSYWAIT_UNTIL_ABS(!(cca_status &= NETSTACK_RADIO.channel_clear()),
+                           current_slot_start, tsch_timing[tsch_ts_cca_offset] + tsch_timing[tsch_ts_cca]);
         TSCH_DEBUG_TX_EVENT();
         /* there is not enough time to turn radio off */
         /*  NETSTACK_RADIO.off(); */
         if(cca_status == 0) {
           mac_tx_status = MAC_TX_COLLISION;
         } else
-#endif /* CCA_ENABLED */
+#endif /* TSCH_CCA_ENABLED */
         {
           /* delay before TX */
           TSCH_SCHEDULE_AND_YIELD(pt, t, current_slot_start, tsch_timing[tsch_ts_tx_offset] - RADIO_DELAY_BEFORE_TX, "TxBeforeTx");