diff --git a/cpu/cc2538/radio/cc2538_rf_radio_ops.c b/cpu/cc2538/radio/cc2538_rf_radio_ops.c
index a1505262950e..2780fbf12969 100644
--- a/cpu/cc2538/radio/cc2538_rf_radio_ops.c
+++ b/cpu/cc2538/radio/cc2538_rf_radio_ops.c
@@ -619,6 +619,7 @@ void cc2538_rf_hal_setup(ieee802154_dev_t *hal)
 
 static const ieee802154_radio_ops_t cc2538_rf_ops = {
     .caps = IEEE802154_CAP_24_GHZ
+          | IEEE802154_CAP_AUTO_ACK
           | IEEE802154_CAP_AUTO_CSMA
           | IEEE802154_CAP_IRQ_CRC_ERROR
           | IEEE802154_CAP_IRQ_TX_DONE
diff --git a/cpu/esp32/esp-ieee802154/esp_ieee802154_hal.c b/cpu/esp32/esp-ieee802154/esp_ieee802154_hal.c
index 8754fa62b5fd..b4be883079c5 100644
--- a/cpu/esp32/esp-ieee802154/esp_ieee802154_hal.c
+++ b/cpu/esp32/esp-ieee802154/esp_ieee802154_hal.c
@@ -438,6 +438,7 @@ int esp_ieee802154_init(void)
 static const ieee802154_radio_ops_t esp_ieee802154_driver = {
     .caps = IEEE802154_CAP_24_GHZ
           | IEEE802154_CAP_PHY_OQPSK
+          | IEEE802154_CAP_AUTO_ACK
           | IEEE802154_CAP_AUTO_CSMA
           | IEEE802154_CAP_SRC_ADDR_MATCH
 #if _USE_CCA_DONE
diff --git a/cpu/native/Makefile.dep b/cpu/native/Makefile.dep
index cd33b6ea55fa..2921b4c70b59 100644
--- a/cpu/native/Makefile.dep
+++ b/cpu/native/Makefile.dep
@@ -37,6 +37,7 @@ ifneq (,$(filter socket_zep,$(USEMODULE)))
   USEMODULE += ieee802154
   ifneq (,$(filter netdev,$(USEMODULE)))
     USEMODULE += netdev_ieee802154_submac
+    USEMODULE += netdev_ieee802154_submac_soft_ack
   endif
 endif
 
diff --git a/cpu/native/socket_zep/socket_zep.c b/cpu/native/socket_zep/socket_zep.c
index 751c5d3ca1e4..c1a5a00ae04a 100644
--- a/cpu/native/socket_zep/socket_zep.c
+++ b/cpu/native/socket_zep/socket_zep.c
@@ -257,37 +257,6 @@ static void _send_zep_hello(socket_zep_t *dev)
     }
 }
 
-static void _send_ack(void *arg)
-{
-    ieee802154_dev_t *dev = arg;
-    socket_zep_t *zepdev = dev->priv;
-    const uint8_t *rxbuf = &zepdev->rcv_buf[sizeof(zep_v2_data_hdr_t)];
-    uint8_t ack[3];
-    zep_v2_data_hdr_t hdr;
-
-    /* sending ACK should only happen if we received a frame */
-    assert(zepdev->state == ZEPDEV_STATE_RX_RECV);
-    /* ACK request bit should be set if we get here */
-    assert((rxbuf[0] & IEEE802154_FCF_ACK_REQ) != 0);
-
-    DEBUG("socket_zep::send_ack: seq_no: %u\n", rxbuf[2]);
-
-    _zep_hdr_fill(zepdev, &hdr.hdr, sizeof(ack) + IEEE802154_FCF_LEN);
-
-    ack[0] = IEEE802154_FCF_TYPE_ACK; /* FCF */
-    ack[1] = 0; /* FCF */
-    ack[2] = rxbuf[2];  /* SeqNum */
-
-    /* calculate checksum */
-    uint16_t chksum = crc16_ccitt_false_update(0, ack, 3);
-
-    real_send(zepdev->sock_fd, &hdr, sizeof(hdr), MSG_MORE);
-    real_send(zepdev->sock_fd, ack, sizeof(ack), MSG_MORE);
-    real_send(zepdev->sock_fd, &chksum, sizeof(chksum), 0);
-
-    dev->cb(dev, IEEE802154_RADIO_INDICATION_RX_DONE);
-}
-
 static void _send_frame(void *arg)
 {
     ieee802154_dev_t *dev = arg;
@@ -359,13 +328,7 @@ static void _socket_isr(int fd, void *arg)
     zepdev->rcv_len = res;
     dev->cb(dev, IEEE802154_RADIO_INDICATION_RX_START);
 
-    /* send ACK after 192 µs */
-    if ((((uint8_t *)(zep + 1))[0] & IEEE802154_FCF_ACK_REQ) != 0) {
-        zepdev->ack_timer.callback = _send_ack;
-        ztimer_set(ZTIMER_USEC, &zepdev->ack_timer, ACK_DELAY_US);
-    } else {
-        dev->cb(dev, IEEE802154_RADIO_INDICATION_RX_DONE);
-    }
+    dev->cb(dev, IEEE802154_RADIO_INDICATION_RX_DONE);
 
     return;
 out:
@@ -505,6 +468,13 @@ static int _set_frame_filter_mode(ieee802154_dev_t *dev, ieee802154_filter_mode_
     return 0;
 }
 
+static int _get_frame_filter_mode(ieee802154_dev_t *dev, ieee802154_filter_mode_t *mode)
+{
+    socket_zep_t *zepdev = dev->priv;
+    *mode = zepdev->filter_mode;
+    return 0;
+}
+
 static int _write(ieee802154_dev_t *dev, const iolist_t *iolist)
 {
     socket_zep_t *zepdev = dev->priv;
@@ -544,7 +514,7 @@ static int _request_transmit(ieee802154_dev_t *dev)
     zepdev->state = ZEPDEV_STATE_TX;
 
     /* 8 bit are mapped to 2 symbols */
-    unsigned time_tx = 2 * zepdev->snd_len * IEEE802154_SYMBOL_TIME_US;
+    unsigned time_tx = 2 * (zepdev->snd_len - sizeof(zep_v2_data_hdr_t)) * IEEE802154_SYMBOL_TIME_US;
     DEBUG("socket_zep::request_transmit(%u bytes, %u µs)\n", zepdev->snd_len, time_tx);
 
     dev->cb(dev, IEEE802154_RADIO_INDICATION_TX_START);
@@ -560,7 +530,14 @@ static int _confirm_transmit(ieee802154_dev_t *dev, ieee802154_tx_info_t *info)
 {
     (void) dev;
 
+    socket_zep_t *zepdev = dev->priv;
+
+    if (zepdev->state == ZEPDEV_STATE_TX) {
+        DEBUG("socket_zep::confirm_transmit: still in TX state\n");
+        return -EAGAIN; /* TX is still in progress */
+    }
     if (info) {
+        DEBUG("socket_zep::confirm_transmit: success\n");
         info->status = TX_STATUS_SUCCESS;
     }
 
@@ -628,6 +605,7 @@ static int _request_op(ieee802154_dev_t *dev, ieee802154_hal_op_t op, void *ctx)
     switch (op) {
     case IEEE802154_HAL_OP_TRANSMIT:
         if (zepdev->state != ZEPDEV_STATE_IDLE) {
+            DEBUG("socket_zep::request_op: request TX in state %u (busy)\n", zepdev->state);
             return -EBUSY;
         }
         res = _request_transmit(dev);
@@ -659,6 +637,7 @@ static int _request_op(ieee802154_dev_t *dev, ieee802154_hal_op_t op, void *ctx)
             ztimer_remove(ZTIMER_USEC, &zepdev->ack_timer);
             zepdev->state = ZEPDEV_STATE_IDLE;
         } else {
+            DEBUG("socket_zep::request_op: request IDLE in state TX\n");
             return -EBUSY;
         }
 
@@ -723,6 +702,7 @@ static const ieee802154_radio_ops_t socket_zep_rf_ops = {
     .config_src_addr_match = _config_src_addr_match,
     .set_csma_params = _set_csma_params,
     .set_frame_filter_mode = _set_frame_filter_mode,
+    .get_frame_filter_mode = _get_frame_filter_mode,
 };
 
 void socket_zep_hal_setup(socket_zep_t *dev, ieee802154_dev_t *hal)
diff --git a/cpu/nrf52/Makefile.dep b/cpu/nrf52/Makefile.dep
index 52a3444b4fdc..e474509e6aae 100644
--- a/cpu/nrf52/Makefile.dep
+++ b/cpu/nrf52/Makefile.dep
@@ -14,6 +14,7 @@ ifneq (,$(filter nrf802154,$(USEMODULE)))
   USEMODULE += luid
   ifneq (,$(filter netdev,$(USEMODULE)))
     USEMODULE += netdev_ieee802154_submac
+    USEMODULE += netdev_ieee802154_submac_soft_ack
   endif
 endif
 
diff --git a/cpu/nrf52/radio/nrf802154/nrf802154_radio.c b/cpu/nrf52/radio/nrf802154/nrf802154_radio.c
index 404a6e676650..dfb5b293007c 100644
--- a/cpu/nrf52/radio/nrf802154/nrf802154_radio.c
+++ b/cpu/nrf52/radio/nrf802154/nrf802154_radio.c
@@ -69,7 +69,6 @@
 
 static uint8_t rxbuf[IEEE802154_FRAME_LEN_MAX + 3]; /* len PHR + PSDU + LQI */
 static uint8_t txbuf[IEEE802154_FRAME_LEN_MAX + 3]; /* len PHR + PSDU + LQI */
-static uint8_t ack[IEEE802154_ACK_FRAME_LEN];
 
 typedef enum {
     STATE_IDLE,
@@ -430,30 +429,6 @@ static void _set_ifs_timer(bool lifs)
     timer_start(NRF802154_TIMER);
 }
 
-static void _timer_cb(void *arg, int chan)
-{
-    (void)arg;
-    ieee802154_dev_t *dev = nrf802154_hal_dev;
-
-    if (chan == MAC_TIMER_CHAN_ACK) {
-        /* Copy sqn */
-        ack[1] = IEEE802154_FCF_TYPE_ACK;
-        if (cfg.pending) {
-            ack[1] |= IEEE802154_FCF_FRAME_PEND;
-        }
-
-        ack[3] = rxbuf[3];
-
-        NRF_RADIO->PACKETPTR = (uint32_t) &ack;
-        NRF_RADIO->TASKS_TXEN = 1;
-        dev->cb(dev, IEEE802154_RADIO_INDICATION_RX_DONE);
-    }
-    else if (chan == MAC_TIMER_CHAN_IFS) {
-        cfg.ifs = false;
-    }
-
-    timer_stop(NRF802154_TIMER);
-}
 /**
  * @brief   Set radio into DISABLED state
  */
@@ -463,16 +438,6 @@ int nrf802154_init(void)
     /* reset buffer */
     rxbuf[0] = 0;
     txbuf[0] = 0;
-
-    ack[0] = IEEE802154_ACK_FRAME_LEN; /* PSDU length */
-    ack[1] = IEEE802154_FCF_TYPE_ACK; /* FCF */
-    ack[2] = 0; /* FCF */
-
-    int result = timer_init(NRF802154_TIMER, TIMER_FREQ, _timer_cb, NULL);
-    assert(result >= 0);
-    (void)result;
-    timer_stop(NRF802154_TIMER);
-
     /* power off peripheral (but do not release the HFXO as we never requested
      * it so far) */
     NRF_RADIO->POWER = 0;
@@ -528,9 +493,7 @@ void isr_radio(void)
         case STATE_RX:
             if (NRF_RADIO->CRCSTATUS) {
                 bool l2filter_passed = _l2filter(rxbuf+1);
-                bool is_auto_ack_en = !IS_ACTIVE(CONFIG_IEEE802154_AUTO_ACK_DISABLE);
                 bool is_ack = rxbuf[1] & IEEE802154_FCF_TYPE_ACK;
-                bool ack_req = rxbuf[1] & IEEE802154_FCF_ACK_REQ;
 
                 /* If radio is in promiscuos mode, indicate packet and
                  * don't event think of sending an ACK frame :) */
@@ -543,17 +506,9 @@ void isr_radio(void)
                  * directly or if the driver should send an ACK frame before
                  * the indication */
                 else if (l2filter_passed) {
-                    if (ack_req && is_auto_ack_en) {
-                        timer_set(NRF802154_TIMER, MAC_TIMER_CHAN_ACK, IEEE802154_SIFS_SYMS);
-                        timer_start(NRF802154_TIMER);
-                        _disable();
-                        _state = STATE_ACK;
-                    }
-                    else {
-                        DEBUG("[nrf802154] RX frame doesn't require ACK frame.\n");
-                        _state = STATE_IDLE;
-                        dev->cb(dev, IEEE802154_RADIO_INDICATION_RX_DONE);
-                    }
+                    DEBUG("[nrf802154] RX frame doesn't require ACK frame.\n");
+                    _state = STATE_IDLE;
+                    dev->cb(dev, IEEE802154_RADIO_INDICATION_RX_DONE);
                 }
                 /* In case the packet is an ACK and the ACK filter is disabled,
                  * indicate the frame reception */
@@ -770,6 +725,21 @@ static int _set_frame_filter_mode(ieee802154_dev_t *dev, ieee802154_filter_mode_
     return 0;
 }
 
+static int _get_frame_filter_mode(ieee802154_dev_t *dev, ieee802154_filter_mode_t *mode)
+{
+    (void) dev;
+    if (cfg.promisc) {
+        *mode = IEEE802154_FILTER_PROMISC;
+    }
+    else if (!cfg.ack_filter) {
+        *mode = IEEE802154_FILTER_ACK_ONLY;
+    }
+    else {
+        *mode = IEEE802154_FILTER_ACCEPT;
+    }
+    return 0;
+}
+
 static int _set_csma_params(ieee802154_dev_t *dev, const ieee802154_csma_be_t *bd,
                             int8_t retries)
 {
@@ -823,4 +793,5 @@ static const ieee802154_radio_ops_t nrf802154_ops = {
     .config_addr_filter = _config_addr_filter,
     .config_src_addr_match = _config_src_addr_match,
     .set_frame_filter_mode = _set_frame_filter_mode,
+    .get_frame_filter_mode = _get_frame_filter_mode,
 };
diff --git a/drivers/include/net/netdev/ieee802154_submac.h b/drivers/include/net/netdev/ieee802154_submac.h
index ca623d931005..87f2d39e32c2 100644
--- a/drivers/include/net/netdev/ieee802154_submac.h
+++ b/drivers/include/net/netdev/ieee802154_submac.h
@@ -49,7 +49,7 @@ typedef struct {
     netdev_ieee802154_t dev;            /**< IEEE 802.15.4 netdev descriptor */
     ieee802154_submac_t submac;         /**< IEEE 802.15.4 SubMAC descriptor */
     ztimer_t ack_timer;                 /**< ztimer descriptor for the ACK timeout timer */
-    int isr_flags;                      /**< netdev submac @ref NETDEV_EVENT_ISR flags */
+    uint32_t isr_flags;                 /**< netdev submac @ref NETDEV_EVENT_ISR flags */
     int bytes_tx;                       /**< size of the sent frame or tx error */
     int8_t retrans;                     /**< number of frame retransmissions of the last TX */
     bool dispatch;                      /**< whether an event should be dispatched or not */
diff --git a/drivers/kw2xrf/kw2xrf_radio_hal.c b/drivers/kw2xrf/kw2xrf_radio_hal.c
index e66f47bfb00d..be6da4d2567e 100644
--- a/drivers/kw2xrf/kw2xrf_radio_hal.c
+++ b/drivers/kw2xrf/kw2xrf_radio_hal.c
@@ -705,6 +705,7 @@ static int _set_csma_params(ieee802154_dev_t *dev, const ieee802154_csma_be_t *b
 
 static const ieee802154_radio_ops_t kw2xrf_ops = {
     .caps =  IEEE802154_CAP_24_GHZ
+          | IEEE802154_CAP_AUTO_ACK
           | IEEE802154_CAP_IRQ_CRC_ERROR
           | IEEE802154_CAP_IRQ_RX_START
           | IEEE802154_CAP_IRQ_TX_DONE
diff --git a/drivers/mrf24j40/mrf24j40_radio_hal.c b/drivers/mrf24j40/mrf24j40_radio_hal.c
index ee01f9c68a4f..0cfb1ceaeff7 100644
--- a/drivers/mrf24j40/mrf24j40_radio_hal.c
+++ b/drivers/mrf24j40/mrf24j40_radio_hal.c
@@ -343,6 +343,7 @@ int _set_frame_retrans(ieee802154_dev_t *hal, uint8_t retrans)
 
 static const ieee802154_radio_ops_t mrf24j40_ops = {
     .caps =  IEEE802154_CAP_24_GHZ
+          | IEEE802154_CAP_AUTO_ACK
           | IEEE802154_CAP_IRQ_TX_DONE
           | IEEE802154_CAP_FRAME_RETRANS
           | IEEE802154_CAP_FRAME_RETRANS_INFO
diff --git a/drivers/netdev_ieee802154_submac/Makefile.include b/drivers/netdev_ieee802154_submac/Makefile.include
new file mode 100644
index 000000000000..3b3230fef92c
--- /dev/null
+++ b/drivers/netdev_ieee802154_submac/Makefile.include
@@ -0,0 +1 @@
+PSEUDOMODULES += netdev_ieee802154_submac_soft_ack
diff --git a/drivers/netdev_ieee802154_submac/netdev_ieee802154_submac.c b/drivers/netdev_ieee802154_submac/netdev_ieee802154_submac.c
index 9a96cb4ec66d..32bc07cc64cb 100644
--- a/drivers/netdev_ieee802154_submac/netdev_ieee802154_submac.c
+++ b/drivers/netdev_ieee802154_submac/netdev_ieee802154_submac.c
@@ -13,20 +13,39 @@
  * @author José I. Alamos <jose.alamos@haw-hamburg.de>
  */
 
+#include <assert.h>
+#include <stdint.h>
+
+#include "atomic_utils.h"
+#include "irq.h"
+#include "net/ieee802154/radio.h"
 #include "net/netdev/ieee802154_submac.h"
 #include "event/thread.h"
 
+#define ENABLE_DEBUG 0
+#include "debug.h"
+
 static const ieee802154_submac_cb_t _cb;
 
 static const netdev_driver_t netdev_submac_driver;
 
+static uint32_t _isr_flags_get_clear(netdev_ieee802154_submac_t *netdev_submac, uint32_t clear)
+{
+    return atomic_fetch_and_u32(&netdev_submac->isr_flags, ~clear);
+}
+
+static void _isr_flags_set(netdev_ieee802154_submac_t *netdev_submac, uint32_t set)
+{
+    atomic_fetch_or_u32(&netdev_submac->isr_flags, set);
+}
+
 static void _ack_timeout(void *arg)
 {
     netdev_ieee802154_submac_t *netdev_submac = arg;
     netdev_t *netdev = arg;
 
-    netdev_submac->isr_flags |= NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT;
-
+    _isr_flags_set(netdev_submac, NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT);
+    DEBUG("IEEE802154 submac: _ack_timeout(): post NETDEV_EVENT_ISR\n");
     netdev->event_callback(netdev, NETDEV_EVENT_ISR);
 }
 
@@ -137,8 +156,8 @@ void ieee802154_submac_bh_request(ieee802154_submac_t *submac)
                                                              submac);
 
     netdev_t *netdev = &netdev_submac->dev.netdev;
-    netdev_submac->isr_flags |= NETDEV_SUBMAC_FLAGS_BH_REQUEST;
-
+    _isr_flags_set(netdev_submac, NETDEV_SUBMAC_FLAGS_BH_REQUEST);
+    DEBUG("IEEE802154 submac: ieee802154_submac_bh_request(): post NETDEV_EVENT_ISR\n");
     netdev->event_callback(netdev, NETDEV_EVENT_ISR);
 }
 
@@ -147,7 +166,8 @@ void ieee802154_submac_ack_timer_set(ieee802154_submac_t *submac)
     netdev_ieee802154_submac_t *netdev_submac = container_of(submac,
                                                              netdev_ieee802154_submac_t,
                                                              submac);
-
+    ieee802154_submac_ack_timer_cancel(submac);
+    DEBUG("IEEE802154 submac: Setting ACK timeout %"PRIu16" us\n", submac->ack_timeout_us);
     ztimer_set(ZTIMER_USEC, &netdev_submac->ack_timer, submac->ack_timeout_us);
 }
 
@@ -156,11 +176,10 @@ void ieee802154_submac_ack_timer_cancel(ieee802154_submac_t *submac)
     netdev_ieee802154_submac_t *netdev_submac = container_of(submac,
                                                              netdev_ieee802154_submac_t,
                                                              submac);
-
+    DEBUG("IEEE802154 submac: Removing ACK timeout\n");
     ztimer_remove(ZTIMER_USEC, &netdev_submac->ack_timer);
     /* Prevent a race condition between the RX_DONE event and the ACK timeout */
-    netdev_submac->isr_flags &= ~NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT;
-
+    _isr_flags_get_clear(netdev_submac, NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT);
 }
 
 static int _send(netdev_t *netdev, const iolist_t *pkt)
@@ -189,59 +208,68 @@ static void _isr(netdev_t *netdev)
                                                              dev);
     ieee802154_submac_t *submac = &netdev_submac->submac;
 
-    bool can_dispatch = true;
+    uint32_t flags;
     do {
-        irq_disable();
-        int flags = netdev_submac->isr_flags;
-        netdev_submac->isr_flags = 0;
-        irq_enable();
-
-        if (flags & NETDEV_SUBMAC_FLAGS_BH_REQUEST) {
-            ieee802154_submac_bh_process(submac);
+        flags = _isr_flags_get_clear(netdev_submac, NETDEV_SUBMAC_FLAGS_CRC_ERROR);
+        if (flags & NETDEV_SUBMAC_FLAGS_CRC_ERROR) {
+            DEBUG("IEEE802154 submac:c NETDEV_SUBMAC_FLAGS_CRC_ERROR\n");
+            ieee802154_submac_crc_error_cb(submac);
+            flags &= ~NETDEV_SUBMAC_FLAGS_CRC_ERROR;
+            continue;
         }
 
+        flags = _isr_flags_get_clear(netdev_submac, NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT);
         if (flags & NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT) {
-            ieee802154_submac_ack_timeout_fired(&netdev_submac->submac);
+            DEBUG("IEEE802154 submac: _isr(): NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT\n");
+            ieee802154_submac_ack_timeout_fired(submac);
+            flags &= ~NETDEV_SUBMAC_FLAGS_ACK_TIMEOUT;
+            continue;
         }
 
-        if (flags & NETDEV_SUBMAC_FLAGS_TX_DONE) {
-            ieee802154_submac_tx_done_cb(&netdev_submac->submac);
+        flags = _isr_flags_get_clear(netdev_submac, NETDEV_SUBMAC_FLAGS_BH_REQUEST);
+        if (flags & NETDEV_SUBMAC_FLAGS_BH_REQUEST) {
+            DEBUG("IEEE802154 submac: _isr(): NETDEV_SUBMAC_FLAGS_BH_REQUEST\n");
+            ieee802154_submac_bh_process(submac);
+            flags &= ~NETDEV_SUBMAC_FLAGS_BH_REQUEST;
+            continue;
         }
 
+        flags = _isr_flags_get_clear(netdev_submac, NETDEV_SUBMAC_FLAGS_RX_DONE);
         if (flags & NETDEV_SUBMAC_FLAGS_RX_DONE) {
+            DEBUG("IEEE802154 submac: _isr(): NETDEV_SUBMAC_FLAGS_RX_DONE\n");
             ieee802154_submac_rx_done_cb(submac);
+            flags &= ~NETDEV_SUBMAC_FLAGS_RX_DONE;
+            /* dispatch to netif */
         }
 
-        if (flags & NETDEV_SUBMAC_FLAGS_CRC_ERROR) {
-            ieee802154_submac_crc_error_cb(submac);
+        flags = _isr_flags_get_clear(netdev_submac, NETDEV_SUBMAC_FLAGS_TX_DONE);
+        if (flags & NETDEV_SUBMAC_FLAGS_TX_DONE) {
+            DEBUG("IEEE802154 submac: _isr(): NETDEV_SUBMAC_FLAGS_TX_DONE\n");
+            ieee802154_submac_tx_done_cb(submac);
+            flags &= ~NETDEV_SUBMAC_FLAGS_TX_DONE;
+            /* dispatch to netif */
         }
 
-        if (flags) {
-            can_dispatch = false;
-        }
+        DEBUG("IEEE802154 submac: _isr_flags_get_clear(): pending flags: %"PRIu32"\n", flags);
+        assert(!flags);
+        break;
 
-    } while (netdev_submac->isr_flags != 0);
+    } while (1);
 
     if (netdev_submac->dispatch) {
-        /* The SubMAC will not generate further events after calling TX Done
-         * or RX Done, but there might be pending ISR events that might not be
-         * caught by the previous loop.
-         * This should be safe to make sure that all events are cached */
-        if (!can_dispatch) {
-            netdev->event_callback(netdev, NETDEV_EVENT_ISR);
-            return;
-        }
+        /* The SubMAC will not generate further events after calling TX Done or RX Done. */
         netdev_submac->dispatch = false;
         /* TODO: Prevent race condition when state goes to PREPARE */
+        DEBUG("IEEE802154 submac: _isr(): dispatching %d\n", netdev_submac->ev);
         netdev->event_callback(netdev, netdev_submac->ev);
         /* HACK: the TX_STARTED event is used to indicate a frame was
          * sent during the event callback.
          * If no frame was sent go back to RX */
-        if (netdev_submac->ev != NETDEV_EVENT_TX_STARTED) {
-            ieee802154_set_rx(submac);
-        }
+        ieee802154_set_rx(submac);
+    }
+    else {
+        DEBUG("IEEE802154 submac: no events to dispatch\n");
     }
-
 }
 
 static int _recv(netdev_t *netdev, void *buf, size_t len, void *info)
@@ -268,7 +296,30 @@ static int _recv(netdev_t *netdev, void *buf, size_t len, void *info)
 
         netdev_rx_info->lqi = rx_info.lqi;
     }
-
+#if IS_USED(MODULE_NETDEV_IEEE802154_SUBMAC_SOFT_ACK)
+    const uint8_t *mhr = buf;
+    if ((mhr[0] & IEEE802154_FCF_TYPE_MASK) == IEEE802154_FCF_TYPE_DATA &&
+        (mhr[0] & IEEE802154_FCF_ACK_REQ)) {
+        ieee802154_filter_mode_t mode;
+        if (!ieee802154_radio_has_capability(&submac->dev, IEEE802154_CAP_AUTO_ACK) &&
+            (ieee802154_radio_get_frame_filter_mode(&submac->dev, &mode) < 0
+                || mode == IEEE802154_FILTER_ACCEPT)) {
+            /* send ACK if not handled by the driver and not in promiscuous mode */
+            uint8_t ack[IEEE802154_ACK_FRAME_LEN - IEEE802154_FCS_LEN]
+                = { IEEE802154_FCF_TYPE_ACK, 0x00, ieee802154_get_seq(mhr) };
+            iolist_t io = {
+                .iol_base = ack,
+                .iol_len = sizeof(ack),
+                .iol_next = NULL
+            };
+            DEBUG("IEEE802154 submac: Sending ACK\n");
+            int snd = _send(netdev, &io);
+            if (snd < 0) {
+                DEBUG("IEEE802154 submac: failed to send ACK (%d)\n", snd);
+            }
+        }
+    }
+#endif
     return res;
 }
 
@@ -282,17 +333,22 @@ static void submac_tx_done(ieee802154_submac_t *submac, int status,
     if (info) {
         netdev_submac->retrans = info->retrans;
     }
-
+    assert(!netdev_submac->dispatch);
     netdev_submac->dispatch = true;
     netdev_submac->ev = NETDEV_EVENT_TX_COMPLETE;
 
     switch (status) {
     case TX_STATUS_MEDIUM_BUSY:
+        DEBUG("IEEE802154 submac: NETDEV_EVENT_TX_MEDIUM_BUSY\n");
         netdev_submac->bytes_tx = -EBUSY;
         break;
     case TX_STATUS_NO_ACK:
+        DEBUG("IEEE802154 submac: NETDEV_EVENT_TX_NOACK\n");
         netdev_submac->bytes_tx = -EHOSTUNREACH;
         break;
+    default:
+        DEBUG("IEEE802154 submac: TX complete status: %d\n", status);
+        break;
     }
 }
 
@@ -301,7 +357,9 @@ static void submac_rx_done(ieee802154_submac_t *submac)
     netdev_ieee802154_submac_t *netdev_submac = container_of(submac,
                                                              netdev_ieee802154_submac_t,
                                                              submac);
+    assert(!netdev_submac->dispatch);
     netdev_submac->dispatch = true;
+    DEBUG("IEEE802154 submac: NETDEV_EVENT_RX_COMPLETE\n");
     netdev_submac->ev = NETDEV_EVENT_RX_COMPLETE;
 }
 
@@ -319,19 +377,24 @@ static void _hal_radio_cb(ieee802154_dev_t *dev, ieee802154_trx_ev_t status)
                                                              submac);
     netdev_t *netdev = &netdev_submac->dev.netdev;
 
+    DEBUG("IEEE802154 submac: _hal_radio_cb():\n");
     switch (status) {
     case IEEE802154_RADIO_CONFIRM_TX_DONE:
-        netdev_submac->isr_flags |= NETDEV_SUBMAC_FLAGS_TX_DONE;
+        DEBUG("IEEE802154 submac: _hal_radio_cb(): IEEE802154_RADIO_CONFIRM_TX_DONE\n");
+        _isr_flags_set(netdev_submac, NETDEV_SUBMAC_FLAGS_TX_DONE);
         break;
     case IEEE802154_RADIO_INDICATION_RX_DONE:
-        netdev_submac->isr_flags |= NETDEV_SUBMAC_FLAGS_RX_DONE;
+        DEBUG("IEEE802154 submac: _hal_radio_cb(): IEEE802154_RADIO_INDICATION_RX_DONE\n");
+        _isr_flags_set(netdev_submac, NETDEV_SUBMAC_FLAGS_RX_DONE);
         break;
     case IEEE802154_RADIO_INDICATION_CRC_ERROR:
-        netdev_submac->isr_flags |= NETDEV_SUBMAC_FLAGS_CRC_ERROR;
+        DEBUG("IEEE802154 submac: _hal_radio_cb(): IEEE802154_RADIO_INDICATION_CRC_ERROR\n");
+        _isr_flags_set(netdev_submac, NETDEV_SUBMAC_FLAGS_CRC_ERROR);
         break;
     default:
         break;
     }
+    DEBUG("IEEE802154 submac: _hal_radio_cb(): post NETDEV_EVENT_ISR\n");
     netdev->event_callback(netdev, NETDEV_EVENT_ISR);
 }
 
diff --git a/sys/include/net/ieee802154/radio.h b/sys/include/net/ieee802154/radio.h
index b5ca731a03f0..9528e9a4dce3 100644
--- a/sys/include/net/ieee802154/radio.h
+++ b/sys/include/net/ieee802154/radio.h
@@ -72,6 +72,13 @@ typedef enum {
      * @ref TX_STATUS_MEDIUM_BUSY.
      */
     IEEE802154_CAP_AUTO_CSMA            = BIT1,
+    /**
+     * @brief the device supports automatic ACK frame transmission
+     *
+     * The device automatically sends an ACK frame when it receives a frame
+     * with the ACK Req bit set.
+     */
+    IEEE802154_CAP_AUTO_ACK             = BIT2,
     /**
      * @brief the device support ACK timeout interrupt
      *
@@ -83,71 +90,71 @@ typedef enum {
      *
      * The ACK frame is not indicated to the upper layer.
      */
-    IEEE802154_CAP_IRQ_ACK_TIMEOUT      = BIT2,
+    IEEE802154_CAP_IRQ_ACK_TIMEOUT      = BIT3,
     /**
      * @brief the device supports the IEEE802.15.4 2.4 GHz band
      *
      * It's assumed that @ref IEEE802154_CAP_IRQ_TX_DONE is present.
      */
-    IEEE802154_CAP_24_GHZ               = BIT3,
+    IEEE802154_CAP_24_GHZ               = BIT4,
     /**
      * @brief the device support the IEEE802.15.4 Sub GHz band
      */
-    IEEE802154_CAP_SUB_GHZ              = BIT4,
+    IEEE802154_CAP_SUB_GHZ              = BIT5,
     /**
      * @brief the device reports reception off frames with invalid CRC.
      */
-    IEEE802154_CAP_IRQ_CRC_ERROR        = BIT5,
+    IEEE802154_CAP_IRQ_CRC_ERROR        = BIT6,
     /**
      * @brief the device reports when the transmission is done
      */
-    IEEE802154_CAP_IRQ_TX_DONE          = BIT6,
+    IEEE802154_CAP_IRQ_TX_DONE          = BIT7,
     /**
      * @brief the device reports the start of a frame (SFD) when received.
      */
-    IEEE802154_CAP_IRQ_RX_START         = BIT7,
+    IEEE802154_CAP_IRQ_RX_START         = BIT8,
     /**
      * @brief the device reports the start of a frame (SFD) was sent.
      */
-    IEEE802154_CAP_IRQ_TX_START         = BIT8,
+    IEEE802154_CAP_IRQ_TX_START         = BIT9,
     /**
      * @brief the device reports the end of the CCA procedure
      */
-    IEEE802154_CAP_IRQ_CCA_DONE         = BIT9,
+    IEEE802154_CAP_IRQ_CCA_DONE         = BIT10,
     /**
      * @brief the device provides the number of retransmissions
      *
      * It's assumed that @ref IEEE802154_CAP_FRAME_RETRANS is present.
      */
-    IEEE802154_CAP_FRAME_RETRANS_INFO   = BIT10,
+    IEEE802154_CAP_FRAME_RETRANS_INFO   = BIT11,
     /**
      * @brief the device retains all register values when off.
      */
-    IEEE802154_CAP_REG_RETENTION        = BIT11,
+    IEEE802154_CAP_REG_RETENTION        = BIT12,
     /**
      * @brief Binary Phase Shift Keying PHY mode
      */
-    IEEE802154_CAP_PHY_BPSK             = BIT12,
+    IEEE802154_CAP_PHY_BPSK             = BIT13,
     /**
      * @brief Amplitude-Shift Keying PHY mode
      */
-    IEEE802154_CAP_PHY_ASK              = BIT13,
+    IEEE802154_CAP_PHY_ASK              = BIT14,
     /**
      * @brief Offset Quadrature Phase-Shift Keying
      */
-    IEEE802154_CAP_PHY_OQPSK            = BIT14,
+    IEEE802154_CAP_PHY_OQPSK            = BIT15,
     /**
      * @brief Multi-Rate Offset Quadrature Phase-Shift Keying PHY mode
      */
-    IEEE802154_CAP_PHY_MR_OQPSK         = BIT15,
+    IEEE802154_CAP_PHY_MR_OQPSK         = BIT16,
     /**
      * @brief Multi-Rate Orthogonal Frequency-Division Multiplexing PHY mode
      */
-    IEEE802154_CAP_PHY_MR_OFDM          = BIT16,
+    IEEE802154_CAP_PHY_MR_OFDM          = BIT17,
     /**
      * @brief Multi-Rate Frequency Shift Keying PHY mode
      */
-    IEEE802154_CAP_PHY_MR_FSK           = BIT17,
+    IEEE802154_CAP_PHY_MR_FSK           = BIT18,
     /**
      * @brief the device supports source address match table.
      *
@@ -156,7 +163,7 @@ typedef enum {
      * Request command from a child node, the Frame Pending bit of the ACK is
      * set if the source address matches one from the table.
      */
-    IEEE802154_CAP_SRC_ADDR_MATCH       = BIT18,
+    IEEE802154_CAP_SRC_ADDR_MATCH       = BIT19,
 } ieee802154_rf_caps_t;
 
 /**
@@ -532,8 +539,8 @@ struct ieee802154_radio_ops {
      * @param[in] dev IEEE802.15.4 device descriptor
      * @param[in] psdu PSDU frame to be sent
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*write)(ieee802154_dev_t *dev, const iolist_t *psdu);
 
@@ -572,8 +579,8 @@ struct ieee802154_radio_ops {
      * @param[in] info information of the received frame (LQI, RSSI). Can be
      *            NULL if this information is not needed.
      *
-     * @return number of bytes written in @p buffer (0 if @p buf == NULL)
-     * @return -ENOBUFS if the frame doesn't fit in @p
+     * @retval number of bytes written in @p buffer (0 if @p buf == NULL)
+     * @retval -ENOBUFS if the frame doesn't fit in @p buf
      */
     int (*read)(ieee802154_dev_t *dev, void *buf, size_t size, ieee802154_rx_info_t *info);
     /**
@@ -585,8 +592,8 @@ struct ieee802154_radio_ops {
      *
      * @post the device is off
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*off)(ieee802154_dev_t *dev);
 
@@ -600,8 +607,8 @@ struct ieee802154_radio_ops {
      *
      * @param[in] dev IEEE802.15.4 device descriptor
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*request_on)(ieee802154_dev_t *dev);
 
@@ -627,9 +634,9 @@ struct ieee802154_radio_ops {
      *
      * @param[in] dev IEEE802.15.4 device descriptor
      *
-     * @return 0 if the device is on
-     * @return -EAGAIN if the device is still busy turning on
-     * @return negative errno on error
+     * @retval 0 if the device is on
+     * @retval -EAGAIN if the device is still busy turning on
+     * @retval negative errno on error
      */
     int (*confirm_on)(ieee802154_dev_t *dev);
 
@@ -674,8 +681,8 @@ struct ieee802154_radio_ops {
      * @param[in] dev IEEE802.15.4 device descriptor
      * @param[in] threshold the threshold in dBm.
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*set_cca_threshold)(ieee802154_dev_t *dev, int8_t threshold);
 
@@ -689,9 +696,9 @@ struct ieee802154_radio_ops {
      * @param[in] dev IEEE802.15.4 device descriptor
      * @param[in] mode the CCA mode
      *
-     * @return 0 on success
-     * @return -ENOTSUP if the mode is not supported
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval -ENOTSUP if the mode is not supported
+     * @retval negative errno on error
      */
     int (*set_cca_mode)(ieee802154_dev_t *dev, ieee802154_cca_mode_t mode);
 
@@ -710,9 +717,9 @@ struct ieee802154_radio_ops {
      * @param[in] dev IEEE802.15.4 device descriptor
      * @param[in] conf the PHY configuration
      *
-     * @return 0        on success
-     * @return -EINVAL  if the configuration is not valid for the device.
-     * @return <0       error, return value is negative errno indicating the cause.
+     * @retval 0        on success
+     * @retval -EINVAL  if the configuration is not valid for the device.
+     * @retval <0       error, return value is negative errno indicating the cause.
      */
     int (*config_phy)(ieee802154_dev_t *dev, const ieee802154_phy_conf_t *conf);
 
@@ -727,8 +734,8 @@ struct ieee802154_radio_ops {
      * @param[in] dev IEEE802.15.4 device descriptor
      * @param[in] retrans the number of retransmissions attempts.
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*set_frame_retrans)(ieee802154_dev_t *dev, uint8_t retrans);
 
@@ -746,26 +753,39 @@ struct ieee802154_radio_ops {
      *                    ieee802154_radio_request_transmit function is
      *                    equivalent to CCA send.
      *
-     * @return 0 on success
-     * @return -EINVAL if the settings are not supported.
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval -EINVAL if the settings are not supported.
+     * @retval negative errno on error
      */
     int (*set_csma_params)(ieee802154_dev_t *dev, const ieee802154_csma_be_t *bd,
                            int8_t retries);
 
     /**
-     * @brief Set the frame filter moder.
+     * @brief Set the frame filter mode.
      *
      * @pre the device is on
      *
      * @param[in] dev IEEE802.15.4 device descriptor
      * @param[in] mode address filter mode
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*set_frame_filter_mode)(ieee802154_dev_t *dev, ieee802154_filter_mode_t mode);
 
+    /**
+     * @brief Get the frame filter mode.
+     *
+     * @pre the device is on
+     *
+     * @param[in] dev IEEE802.15.4 device descriptor
+     * @param[out] mode address filter mode
+     *
+     * @retval 0 on success
+     * @retval negative errno on error
+     */
+    int (*get_frame_filter_mode)(ieee802154_dev_t *dev, ieee802154_filter_mode_t *mode);
+
     /**
      * @brief Configure the address filter.
      *
@@ -778,8 +798,8 @@ struct ieee802154_radio_ops {
      * @param[in] cmd command for the address filter
      * @param[in] value value for @p cmd.
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*config_addr_filter)(ieee802154_dev_t *dev, ieee802154_af_cmd_t cmd, const void *value);
 
@@ -798,13 +818,27 @@ struct ieee802154_radio_ops {
      * @param[in] cmd command for the source address match configuration
      * @param[in] value value associated to @p cmd.
      *
-     * @return 0 on success
-     * @return negative errno on error
+     * @retval 0 on success
+     * @retval negative errno on error
      */
     int (*config_src_addr_match)(ieee802154_dev_t *dev, ieee802154_src_match_t cmd,
                                  const void *value);
 };
 
+/**
+ * @brief Check if the device has a specific capability
+ *
+ * @param[in] dev IEEE802.15.4 device descriptor
+ * @param[in] cap capabilities to check for
+ *
+ * @retval true if the device has the capability
+ * @retval false if the device doesn't have the capability
+ */
+static inline bool ieee802154_radio_has_capability(ieee802154_dev_t *dev, uint32_t cap)
+{
+    return (dev->driver->caps & cap) == cap;
+}
+
 /**
  * @brief Shortcut to @ref ieee802154_radio_ops::write
  *
@@ -1014,6 +1048,25 @@ static inline int ieee802154_radio_set_frame_filter_mode(ieee802154_dev_t *dev,
     return dev->driver->set_frame_filter_mode(dev, mode);
 }
 
+/**
+ * @brief Shortcut to @ref ieee802154_radio_ops::get_frame_filter_mode
+ *
+ * @pre the device is on
+ *
+ * @param[in] dev IEEE802.15.4 device descriptor
+ * @param[out] mode frame filter mode
+ *
+ * @return result of @ref ieee802154_radio_ops::get_frame_filter_mode
+ */
+static inline int ieee802154_radio_get_frame_filter_mode(ieee802154_dev_t *dev,
+                                                         ieee802154_filter_mode_t *mode)
+{
+    if (dev->driver->get_frame_filter_mode) {
+        return dev->driver->get_frame_filter_mode(dev, mode);
+    }
+    return -ENOTSUP;
+}
+
 /**
  * @brief Shortcut to @ref ieee802154_radio_ops::set_frame_retrans
  *
diff --git a/sys/net/link_layer/ieee802154/submac.c b/sys/net/link_layer/ieee802154/submac.c
index aae582fdb20b..a1c32bf04257 100644
--- a/sys/net/link_layer/ieee802154/submac.c
+++ b/sys/net/link_layer/ieee802154/submac.c
@@ -130,6 +130,33 @@ static int _handle_fsm_ev_request_tx(ieee802154_submac_t *submac)
     }
 }
 
+static ieee802154_fsm_state_t _fsm_state_prepare(ieee802154_submac_t *submac,
+                                                 ieee802154_fsm_ev_t ev);
+
+static ieee802154_fsm_state_t _fsm_state_tx(ieee802154_submac_t *submac,
+                                            ieee802154_fsm_ev_t ev);
+
+static int _handle_fsm_ev_tx_ack(ieee802154_submac_t *submac)
+{
+    ieee802154_dev_t *dev = &submac->dev;
+
+    /* Set state to TX_ON */
+    int res;
+    if ((res = ieee802154_radio_set_idle(dev, false)) < 0) {
+        return res;
+    }
+    if ((res = ieee802154_radio_write(dev, submac->psdu)) < 0) {
+        return res;
+    }
+    /* skip async Tx request */
+    _fsm_state_prepare(submac, IEEE802154_FSM_EV_BH);
+    /* wait for Tx done */
+    while (_fsm_state_tx(submac, IEEE802154_FSM_EV_TX_DONE) == IEEE802154_FSM_STATE_INVALID) {
+        DEBUG("IEEE802154 submac: wait until ACK sent\n");
+    }
+    return 0;
+}
+
 static ieee802154_fsm_state_t _fsm_state_rx(ieee802154_submac_t *submac, ieee802154_fsm_ev_t ev)
 {
     ieee802154_dev_t *dev = &submac->dev;
@@ -192,7 +219,16 @@ static ieee802154_fsm_state_t _fsm_state_idle(ieee802154_submac_t *submac, ieee8
 
     switch (ev) {
     case IEEE802154_FSM_EV_REQUEST_TX:
-        if (_handle_fsm_ev_request_tx(submac) < 0) {
+        /* An ACK is sent synchronous to prevent that the upper layer (IPv6)
+           can initiate the next transmission which would fail because the transceiver
+           is still busy. */
+        if (submac->psdu->iol_len == IEEE802154_ACK_FRAME_LEN - IEEE802154_FCS_LEN &&
+            (((uint8_t *)submac->psdu->iol_base)[0] & IEEE802154_FCF_TYPE_ACK) &&
+            submac->psdu->iol_next == NULL) {
+            _handle_fsm_ev_tx_ack(submac);
+            return IEEE802154_FSM_STATE_IDLE;
+        }
+        else if (_handle_fsm_ev_request_tx(submac) < 0) {
             return IEEE802154_FSM_STATE_IDLE;
         }
         return IEEE802154_FSM_STATE_PREPARE;
@@ -321,9 +357,10 @@ static ieee802154_fsm_state_t _fsm_state_tx(ieee802154_submac_t *submac, ieee802
 
     switch (ev) {
     case IEEE802154_FSM_EV_TX_DONE:
-        res = ieee802154_radio_confirm_transmit(&submac->dev, &info);
-        assert(res >= 0);
-        return _fsm_state_tx_process_tx_done(submac, &info);
+        if ((res = ieee802154_radio_confirm_transmit(&submac->dev, &info)) >= 0) {
+            return _fsm_state_tx_process_tx_done(submac, &info);
+        }
+        break;
     case IEEE802154_FSM_EV_RX_DONE:
     case IEEE802154_FSM_EV_CRC_ERROR:
         /* This might happen in case there's a race condition between ACK_TIMEOUT
@@ -377,27 +414,33 @@ ieee802154_fsm_state_t ieee802154_submac_process_ev(ieee802154_submac_t *submac,
 
     switch (submac->fsm_state) {
     case IEEE802154_FSM_STATE_RX:
+        DEBUG("IEEE802154 submac: ieee802154_submac_process_ev(): IEEE802154_FSM_STATE_RX + %s\n", str_ev[ev]);
         new_state = _fsm_state_rx(submac, ev);
         break;
     case IEEE802154_FSM_STATE_IDLE:
+        DEBUG("IEEE802154 submac: ieee802154_submac_process_ev(): IEEE802154_FSM_STATE_IDLE + %s\n", str_ev[ev]);
         new_state = _fsm_state_idle(submac, ev);
         break;
     case IEEE802154_FSM_STATE_PREPARE:
+        DEBUG("IEEE802154 submac: ieee802154_submac_process_ev(): IEEE802154_FSM_STATE_PREPARE + %s\n", str_ev[ev]);
         new_state = _fsm_state_prepare(submac, ev);
         break;
     case IEEE802154_FSM_STATE_TX:
+        DEBUG("IEEE802154 submac: ieee802154_submac_process_ev(): IEEE802154_FSM_STATE_TX + %s\n", str_ev[ev]);
         new_state = _fsm_state_tx(submac, ev);
         break;
     case IEEE802154_FSM_STATE_WAIT_FOR_ACK:
+        DEBUG("IEEE802154 submac: ieee802154_submac_process_ev(): IEEE802154_FSM_STATE_WAIT_FOR_ACK + %s\n", str_ev[ev]);
         new_state = _fsm_state_wait_for_ack(submac, ev);
         break;
     default:
+        DEBUG("IEEE802154 submac: ieee802154_submac_process_ev(): INVALID STATE\n");
         new_state = IEEE802154_FSM_STATE_INVALID;
     }
 
     if (new_state == IEEE802154_FSM_STATE_INVALID) {
         _print_debug(submac->fsm_state, new_state, ev);
-        assert(false);
+        new_state = submac->fsm_state;
     }
     submac->fsm_state = new_state;
     return submac->fsm_state;
@@ -408,6 +451,7 @@ int ieee802154_send(ieee802154_submac_t *submac, const iolist_t *iolist)
     ieee802154_fsm_state_t current_state = submac->fsm_state;
 
     if (current_state != IEEE802154_FSM_STATE_RX && current_state != IEEE802154_FSM_STATE_IDLE) {
+        DEBUG("IEEE802154 submac: ieee802154_send(): Sending aborted, current state is %s\n", str_states[current_state]);
         return -EBUSY;
     }
 
@@ -417,6 +461,8 @@ int ieee802154_send(ieee802154_submac_t *submac, const iolist_t *iolist)
 
     uint8_t *buf = iolist->iol_base;
     bool cnf = buf[0] & IEEE802154_FCF_ACK_REQ;
+    bool is_ack = iolist->iol_len == IEEE802154_ACK_FRAME_LEN - IEEE802154_FCS_LEN &&
+                  (buf[0] & IEEE802154_FCF_TYPE_MASK) == IEEE802154_FCF_TYPE_ACK;
 
     submac->wait_for_ack = cnf;
     submac->psdu = iolist;
@@ -424,8 +470,14 @@ int ieee802154_send(ieee802154_submac_t *submac, const iolist_t *iolist)
     submac->csma_retries_nb = 0;
     submac->backoff_mask = (1 << submac->be.min) - 1;
 
-    if (ieee802154_submac_process_ev(submac, IEEE802154_FSM_EV_REQUEST_TX)
+    if (!is_ack && ieee802154_submac_process_ev(submac, IEEE802154_FSM_EV_REQUEST_TX)
         != IEEE802154_FSM_STATE_PREPARE) {
+        DEBUG("IEEE802154 submac: ieee802154_send(): Tx frame failed %s\n", str_states[current_state]);
+        return -EBUSY;
+    }
+    if (is_ack && ieee802154_submac_process_ev(submac, IEEE802154_FSM_EV_REQUEST_TX)
+             != IEEE802154_FSM_STATE_IDLE) {
+        DEBUG("IEEE802154 submac: ieee802154_send(): Tx ACK failed %s\n", str_states[current_state]);
         return -EBUSY;
     }
     return 0;
@@ -809,6 +861,8 @@ int ieee802154_set_rx(ieee802154_submac_t *submac)
         }
         break;
     default:
+        DEBUG("IEEE802154 submac: ieee802154_set_rx(): Setting RX failed, currently in %s\n",
+              str_states[current_state]);
         break;
     }