diff --git a/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.cpp b/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.cpp
index f46cc0c125c1..bcd0e44f17a8 100644
--- a/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.cpp
+++ b/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.cpp
@@ -20,7 +20,7 @@
 #include "CyH4TransportDriver.h"
 #include "mbed_power_mgmt.h"
 #include "drivers/InterruptIn.h"
-#if !defined(CYW43XXX_UNBUFFERED_UART)
+#if !(defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
 #include "cybsp_types.h"
 #endif
 #include "Callback.h"
@@ -34,7 +34,7 @@ namespace cypress_ble {
 using namespace std::chrono_literals;
 
 CyH4TransportDriver::CyH4TransportDriver(PinName tx, PinName rx, PinName cts, PinName rts, PinName bt_power_name, int baud, PinName bt_host_wake_name, PinName bt_device_wake_name, uint8_t host_wake_irq, uint8_t dev_wake_irq) :
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     uart(tx, rx),
 #else
     tx(tx), rx(rx),
@@ -54,7 +54,7 @@ CyH4TransportDriver::CyH4TransportDriver(PinName tx, PinName rx, PinName cts, Pi
 }
 
 CyH4TransportDriver::CyH4TransportDriver(PinName tx, PinName rx, PinName cts, PinName rts, PinName bt_power_name, int baud) :
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     uart(tx, rx),
 #else
     tx(tx), rx(rx),
@@ -116,20 +116,20 @@ void CyH4TransportDriver::bt_host_wake_fall_irq_handler(void)
     }
 }
 
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
 void CyH4TransportDriver::on_controller_irq()
 #else
 static void on_controller_irq(void *callback_arg, cyhal_uart_event_t event)
 #endif
 {
-#if !defined(CYW43XXX_UNBUFFERED_UART)
+#if !(defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     (void)(event);
     cyhal_uart_t *uart_obj = (cyhal_uart_t *)callback_arg;
 #endif
 
     sleep_manager_lock_deep_sleep();
 
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     while (uart.readable()) {
         uint8_t char_received;
         if (uart.read(&char_received, 1)) {
@@ -153,7 +153,7 @@ void CyH4TransportDriver::initialize()
     bt_power = 0;
     rtos::ThisThread::sleep_for(1ms);
 
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     uart.baud(DEF_BT_BAUD_RATE);
 
     uart.format(
@@ -205,7 +205,7 @@ void CyH4TransportDriver::initialize()
 
 void CyH4TransportDriver::terminate()
 {
-#if !defined(CYW43XXX_UNBUFFERED_UART)
+#if !(defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     cyhal_uart_event_t enable_irq_event = (cyhal_uart_event_t)(CYHAL_UART_IRQ_RX_DONE
                                        | CYHAL_UART_IRQ_TX_DONE
                                        | CYHAL_UART_IRQ_RX_NOT_EMPTY
@@ -229,7 +229,7 @@ void CyH4TransportDriver::terminate()
 
     bt_power = 0; //BT_POWER is an output, should not be freed only set inactive
 
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     uart.close();
 #else
     cyhal_uart_free(&uart);
@@ -245,7 +245,7 @@ uint16_t CyH4TransportDriver::write(uint8_t type, uint16_t len, uint8_t *pData)
 
     while (i < len + 1) {
         uint8_t to_write = i == 0 ? type : pData[i - 1];
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
         while (uart.writeable() == 0);
         uart.write(&to_write, 1);
 #else
@@ -254,8 +254,8 @@ uint16_t CyH4TransportDriver::write(uint8_t type, uint16_t len, uint8_t *pData)
 #endif
         ++i;
     }
-#if defined(CYW43XXX_UNBUFFERED_UART)
-    while (uart.writeable() == 0);
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
+    while(uart.is_tx_active() != 0);
 #else
     while(cyhal_uart_is_tx_active(&uart));
 #endif
@@ -294,7 +294,7 @@ void CyH4TransportDriver::deassert_bt_dev_wake()
 
 void CyH4TransportDriver::update_uart_baud_rate(int baud)
 {
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     uart.baud((uint32_t)baud);
 #else
     uint32_t ignore;
diff --git a/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.h b/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.h
index 8babd0abec41..8e78de99ec42 100644
--- a/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.h
+++ b/connectivity/drivers/ble/FEATURE_BLE/COMPONENT_CYW43XXX/CyH4TransportDriver.h
@@ -25,7 +25,7 @@
 #include "drivers/DigitalInOut.h"
 #include "drivers/InterruptIn.h"
 
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
 #include "drivers/UnbufferedSerial.h"
 #else
 #include "cyhal_uart.h"
@@ -86,8 +86,8 @@ class CyH4TransportDriver : public CordioHCITransportDriver {
 private:
     void assert_bt_dev_wake();
     void deassert_bt_dev_wake();
-	
-#if defined(CYW43XXX_UNBUFFERED_UART)
+
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     void on_controller_irq();
 #endif
 
@@ -98,7 +98,7 @@ class CyH4TransportDriver : public CordioHCITransportDriver {
     // However UART APIs does not prevent the BT radio from going to sleep.
     // Use the HAL APIs to prevent the radio from going to sleep until UART transmition is complete.
     // Mbed layer has no API that distinguish between data in HW buffer v.s. data already transmitted.
-#if defined(CYW43XXX_UNBUFFERED_UART)
+#if (defined(CYW43XXX_UNBUFFERED_UART) && DEVICE_SERIAL_ASYNCH)
     mbed::UnbufferedSerial uart;
 #else
     cyhal_uart_t uart;
diff --git a/drivers/include/drivers/SerialBase.h b/drivers/include/drivers/SerialBase.h
index 9288c271e156..33bb7a8741c1 100644
--- a/drivers/include/drivers/SerialBase.h
+++ b/drivers/include/drivers/SerialBase.h
@@ -273,6 +273,12 @@ class SerialBase : private NonCopyable<SerialBase> {
      */
     int set_dma_usage_rx(DMAUsage usage);
 
+    /** Attempts to determine if the serial peripheral is already in use for TX
+     *
+     * @return Non-zero if the TX transaction is ongoing, 0 otherwise
+     */
+    int is_tx_active();
+
 #if !defined(DOXYGEN_ONLY)
 protected:
     void start_read(void *buffer, int buffer_size, char buffer_width, const event_callback_t &callback, int event, unsigned char char_match);
diff --git a/drivers/include/drivers/UnbufferedSerial.h b/drivers/include/drivers/UnbufferedSerial.h
index a330d6e92bc4..dc93e764aeec 100644
--- a/drivers/include/drivers/UnbufferedSerial.h
+++ b/drivers/include/drivers/UnbufferedSerial.h
@@ -211,6 +211,14 @@ class UnbufferedSerial:
      */
     void set_flow_control(Flow type, PinName flow1 = NC, PinName flow2 = NC);
 #endif // DEVICE_SERIAL_FC
+
+#if DEVICE_SERIAL_ASYNCH
+    /** Attempts to determine if the serial peripheral is already in use for TX
+    *
+    * @return Non-zero if the TX transaction is ongoing, 0 otherwise
+    */
+    int is_tx_active();
+#endif // DEVICE_SERIAL_ASYNCH
 };
 
 } // namespace mbed
diff --git a/drivers/source/SerialBase.cpp b/drivers/source/SerialBase.cpp
index 40bf7d0b6187..3b56daff923b 100644
--- a/drivers/source/SerialBase.cpp
+++ b/drivers/source/SerialBase.cpp
@@ -486,6 +486,16 @@ void SerialBase::interrupt_handler_asynch(void)
     }
 }
 
+int SerialBase::is_tx_active(void)
+{
+    int result = 0;
+    lock();
+    result = serial_tx_active(&_serial);
+    unlock();
+
+    return result;
+}
+
 #endif
 
 } // namespace mbed
diff --git a/drivers/source/UnbufferedSerial.cpp b/drivers/source/UnbufferedSerial.cpp
index cc86530344df..43477c06e624 100644
--- a/drivers/source/UnbufferedSerial.cpp
+++ b/drivers/source/UnbufferedSerial.cpp
@@ -122,6 +122,19 @@ void UnbufferedSerial::set_flow_control(Flow type, PinName flow1, PinName flow2)
 }
 #endif // DEVICE_SERIAL_FC
 
+#if DEVICE_SERIAL_ASYNCH
+int UnbufferedSerial::is_tx_active(void)
+{
+    int retval;
+
+    lock();
+    retval = SerialBase::is_tx_active();
+    unlock();
+
+    return retval;
+}
+#endif // DEVICE_SERIAL_ASYNCH
+
 } // namespace mbed
 
 #endif // #if DEVICE_SERIAL
diff --git a/targets/targets.json b/targets/targets.json
index 003a004c0f19..9717c9658836 100644
--- a/targets/targets.json
+++ b/targets/targets.json
@@ -3050,7 +3050,8 @@
         "device_has_add": [
             "USBDEVICE",
             "EMAC",
-            "QSPI"
+            "QSPI",
+            "SERIAL_ASYNCH"
         ],
         "overrides": {
             "system_power_supply": "PWR_SMPS_1V8_SUPPLIES_LDO",