diff --git a/ports/stm32/cyw43_configport.h b/ports/stm32/cyw43_configport.h
index b7137ef61e..4b6dde3c43 100644
--- a/ports/stm32/cyw43_configport.h
+++ b/ports/stm32/cyw43_configport.h
@@ -32,6 +32,7 @@
 #include "py/mperrno.h"
 #include "py/mphal.h"
 #include "extmod/modnetwork.h"
+#include "extint.h"
 #include "pendsv.h"
 #include "sdio.h"
 
@@ -115,6 +116,12 @@ static inline void cyw43_delay_ms(uint32_t ms) {
     }
 }
 
+static inline void cyw43_hal_pin_config_irq_falling(cyw43_hal_pin_obj_t pin, int enable) {
+    if (enable) {
+        extint_set(pin, GPIO_MODE_IT_FALLING);
+    }
+}
+
 static inline void cyw43_sdio_init(void) {
     sdio_init(NVIC_EncodePriority(NVIC_PRIORITYGROUP_4, 14, 0));
 }
diff --git a/ports/stm32/extint.h b/ports/stm32/extint.h
index fddcc2ae7a..84eb876d8d 100644
--- a/ports/stm32/extint.h
+++ b/ports/stm32/extint.h
@@ -66,6 +66,7 @@ void extint_init0(void);
 
 uint extint_register(mp_obj_t pin_obj, uint32_t mode, uint32_t pull, mp_obj_t callback_obj, bool override_callback_obj);
 void extint_register_pin(const pin_obj_t *pin, uint32_t mode, bool hard_irq, mp_obj_t callback_obj);
+void extint_set(const pin_obj_t *pin, uint32_t mode);
 
 void extint_enable(uint line);
 void extint_disable(uint line);