diff --git a/ports/stm32/boardctrl.h b/ports/stm32/boardctrl.h
index 851922f412..c870af32a4 100644
--- a/ports/stm32/boardctrl.h
+++ b/ports/stm32/boardctrl.h
@@ -66,6 +66,18 @@
 #define MICROPY_BOARD_USBD_CDC_RX_EVENT usbd_cdc_rx_event_callback
 #endif
 
+// Called to poll Bluetooth HCI now.
+// Default function defined in mpbthciport.h.
+#ifndef MICROPY_BOARD_BT_HCI_POLL_NOW
+#define MICROPY_BOARD_BT_HCI_POLL_NOW mp_bluetooth_hci_poll_now_default
+#endif
+
+// Called to poll Bluetooth HCI after the given timeout.
+// Default function defined in mpbthciport.h.
+#ifndef MICROPY_BOARD_BT_HCI_POLL_IN_MS
+#define MICROPY_BOARD_BT_HCI_POLL_IN_MS mp_bluetooth_hci_poll_in_ms_default
+#endif
+
 // Constants to return from boardctrl_run_boot_py, boardctrl_run_main_py.
 enum {
     BOARDCTRL_CONTINUE,
diff --git a/ports/stm32/mpbthciport.c b/ports/stm32/mpbthciport.c
index 369c91e303..a1ab3258b6 100644
--- a/ports/stm32/mpbthciport.c
+++ b/ports/stm32/mpbthciport.c
@@ -71,7 +71,7 @@ STATIC void mp_bluetooth_hci_start_polling(void) {
     mp_bluetooth_hci_poll_now();
 }
 
-void mp_bluetooth_hci_poll_in_ms(uint32_t ms) {
+void mp_bluetooth_hci_poll_in_ms_default(uint32_t ms) {
     soft_timer_reinsert(&mp_bluetooth_hci_soft_timer, ms);
 }
 
@@ -92,7 +92,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(run_events_scheduled_task_obj, run_events_sched
 
 // Called periodically (systick) or directly (e.g. UART RX IRQ) in order to
 // request that processing happens ASAP in the scheduler.
-void mp_bluetooth_hci_poll_now(void) {
+void mp_bluetooth_hci_poll_now_default(void) {
     if (!events_task_is_scheduled) {
         events_task_is_scheduled = mp_sched_schedule(MP_OBJ_FROM_PTR(&run_events_scheduled_task_obj), mp_const_none);
         if (!events_task_is_scheduled) {
@@ -104,7 +104,7 @@ void mp_bluetooth_hci_poll_now(void) {
 
 #else // !MICROPY_PY_BLUETOOTH_USE_SYNC_EVENTS
 
-void mp_bluetooth_hci_poll_now(void) {
+void mp_bluetooth_hci_poll_now_default(void) {
     pendsv_schedule_dispatch(PENDSV_DISPATCH_BLUETOOTH_HCI, mp_bluetooth_hci_poll);
 }
 
diff --git a/ports/stm32/mpbthciport.h b/ports/stm32/mpbthciport.h
index 77919ee0e6..d510ab52ad 100644
--- a/ports/stm32/mpbthciport.h
+++ b/ports/stm32/mpbthciport.h
@@ -26,12 +26,24 @@
 #ifndef MICROPY_INCLUDED_STM32_MPBTHCIPORT_H
 #define MICROPY_INCLUDED_STM32_MPBTHCIPORT_H
 
+#include "boardctrl.h"
+
 // Initialise the HCI subsystem (should be called once, early on).
 void mp_bluetooth_hci_init(void);
 
-// Poll the HCI now, or after a certain timeout.
-void mp_bluetooth_hci_poll_now(void);
-void mp_bluetooth_hci_poll_in_ms(uint32_t ms);
+// Default implementations of poll functions (a board can override them).
+void mp_bluetooth_hci_poll_now_default(void);
+void mp_bluetooth_hci_poll_in_ms_default(uint32_t ms);
+
+// Call this to poll the HCI now.
+static inline void mp_bluetooth_hci_poll_now(void) {
+    MICROPY_BOARD_BT_HCI_POLL_NOW();
+}
+
+// Call this to poll the HCI after a certain timeout.
+static inline void mp_bluetooth_hci_poll_in_ms(uint32_t ms) {
+    MICROPY_BOARD_BT_HCI_POLL_IN_MS(ms);
+}
 
 // Must be provided by the stack bindings (e.g. mpnimbleport.c or mpbtstackport.c).
 // Request new data from the uart and pass to the stack, and run pending events/callouts.