2 files changed, 37 insertions, 11 deletions

diff --git a/wirish/ext_interrupts.cpp b/wirish/ext_interrupts.cpp
index a3e61fd..1195ea9 100644
--- a/wirish/ext_interrupts.cpp
+++ b/wirish/ext_interrupts.cpp
@@ -39,13 +39,6 @@
 
 static inline exti_trigger_mode exti_out_mode(ExtIntTriggerMode mode);
 
-/**
- * @brief Attach an interrupt handler to a pin, triggering on the given mode.
- * @param pin     Pin to attach an interrupt handler onto.
- * @param handler Function to call when the external interrupt is triggered.
- * @param mode    Trigger mode for the given interrupt.
- * @see ExtIntTriggerMode
- */
 void attachInterrupt(uint8 pin, voidFuncPtr handler, ExtIntTriggerMode mode) {
     if (pin >= BOARD_NR_GPIO_PINS || !handler) {
         return;
@@ -59,10 +52,21 @@ void attachInterrupt(uint8 pin, voidFuncPtr handler, ExtIntTriggerMode mode) {
                           outMode);
 }
 
-/**
- * @brief Disable any external interrupt attached to a pin.
- * @param pin Pin number to detach any interrupt from.
- */
+void attachInterrupt(uint8 pin, voidArgumentFuncPtr handler, void *arg,
+                     ExtIntTriggerMode mode) {
+    if (pin >= BOARD_NR_GPIO_PINS || !handler) {
+        return;
+    }
+
+    exti_trigger_mode outMode = exti_out_mode(mode);
+
+    exti_attach_callback((exti_num)(PIN_MAP[pin].gpio_bit),
+                          gpio_exti_port(PIN_MAP[pin].gpio_device),
+                          handler,
+                          arg,
+                          outMode);
+}
+
 void detachInterrupt(uint8 pin) {
     if (pin >= BOARD_NR_GPIO_PINS) {
         return;
diff --git a/wirish/include/wirish/ext_interrupts.h b/wirish/include/wirish/ext_interrupts.h
index 933be04..ce1ca03 100644
--- a/wirish/include/wirish/ext_interrupts.h
+++ b/wirish/include/wirish/ext_interrupts.h
@@ -69,6 +69,28 @@ typedef enum ExtIntTriggerMode {
 void attachInterrupt(uint8 pin, voidFuncPtr handler, ExtIntTriggerMode mode);
 
 /**
+ *  @brief Registers an interrupt handler on a pin.
+ *
+ *  The interrupt will be triggered on a given transition on the pin,
+ *  as specified by the mode parameter.  The handler runs in interrupt
+ *  context.  The new handler will replace whatever handler is
+ *  currently registered for the pin, if any.
+ *
+ *  @param pin Pin number
+ *  @param handler Static class member function to run upon external interrupt
+ *                 trigger. The handler should take 1 argument and return void
+ *  @param arg Argument that the handler will be passed when it's called. One
+ *             use of this is to pass the specific instance of the class that
+ *             will handle the interrupt.
+ *  @param mode Type of transition to trigger on, e.g. falling, rising, etc.
+ *
+ *  @sideeffect Registers a handler
+ *  @see detachInterrupt()
+ */
+void attachInterrupt(uint8 pin, voidArgumentFuncPtr handler, void *arg,
+                     ExtIntTriggerMode mode);
+
+/**
  * @brief Disable any registered external interrupt.
  * @param pin Maple pin number
  * @sideeffect unregisters external interrupt handler