diff --git a/ports/stm32/mphalport.h b/ports/stm32/mphalport.h
index 47bb1f8c84..8028782a90 100644
--- a/ports/stm32/mphalport.h
+++ b/ports/stm32/mphalport.h
@@ -96,11 +96,19 @@ static inline mp_uint_t mp_hal_ticks_cpu(void) {
 #define mp_hal_pin_od_high(p)   mp_hal_pin_high(p)
 #define mp_hal_pin_read(p)      (((p)->gpio->IDR >> (p)->pin) & 1)
 #define mp_hal_pin_write(p, v)  ((v) ? mp_hal_pin_high(p) : mp_hal_pin_low(p))
+#define mp_hal_pin_interrupt(pin, handler, trigger, hard) extint_register_pin(pin, trigger, hard, handler)
+
+enum mp_hal_pin_interrupt_trigger {
+    MP_HAL_PIN_TRIGGER_NONE,
+    MP_HAL_PIN_TRIGGER_FALL = GPIO_MODE_IT_FALLING,
+    MP_HAL_PIN_TRIGGER_RISE = GPIO_MODE_IT_RISING,
+};
 
 void mp_hal_gpio_clock_enable(GPIO_TypeDef *gpio);
 void mp_hal_pin_config(mp_hal_pin_obj_t pin, uint32_t mode, uint32_t pull, uint32_t alt);
 bool mp_hal_pin_config_alt(mp_hal_pin_obj_t pin, uint32_t mode, uint32_t pull, uint8_t fn, uint8_t unit);
 void mp_hal_pin_config_speed(mp_hal_pin_obj_t pin_obj, uint32_t speed);
+void extint_register_pin(const pin_obj_t *pin, uint32_t mode, bool hard_irq, mp_obj_t callback_obj);
 
 enum {
     MP_HAL_MAC_WLAN0 = 0,
diff --git a/ports/stm32/mpnetworkport.c b/ports/stm32/mpnetworkport.c
index 2f49328e11..1ce758e7dd 100644
--- a/ports/stm32/mpnetworkport.c
+++ b/ports/stm32/mpnetworkport.c
@@ -50,6 +50,11 @@
 
 #if MICROPY_PY_NETWORK_WIZNET5K
 void wiznet5k_poll(void);
+void wiznet5k_deinit(void);
+
+void wiznet5k_try_poll(void) {
+    pendsv_schedule_dispatch(PENDSV_DISPATCH_WIZNET, wiznet5k_poll);
+}
 #endif
 
 u32_t sys_now(void) {
diff --git a/ports/stm32/pendsv.h b/ports/stm32/pendsv.h
index 0733d355d3..f97581e99a 100644
--- a/ports/stm32/pendsv.h
+++ b/ports/stm32/pendsv.h
@@ -35,6 +35,9 @@ enum {
     #if MICROPY_PY_NETWORK_CYW43
     PENDSV_DISPATCH_CYW43,
     #endif
+    #if MICROPY_PY_NETWORK_WIZNET5K
+    PENDSV_DISPATCH_WIZNET,
+    #endif
     #endif
     #if MICROPY_PY_BLUETOOTH && !MICROPY_PY_BLUETOOTH_USE_SYNC_EVENTS
     PENDSV_DISPATCH_BLUETOOTH_HCI,