diff --git a/src/main.c b/src/main.c
index 976995ba122616750895b83dcc91ce350f0a02c9..16a6d1c57fbe39cf05c81211a39848aa02cf9b46 100644
--- a/src/main.c
+++ b/src/main.c
@@ -209,11 +209,11 @@ int main()
     init_pwm();
     pwm_echo_init();
 
-    gpio_set_irq_enabled_with_callback(27, GPIO_IRQ_LEVEL_HIGH, true, &callback);
+    gpio_set_irq_enabled_with_callback(27, GPIO_IRQ_EDGE_FALL | GPIO_IRQ_EDGE_RISE, true, &callback);
 
     while (1)
     {
-        }
+    }
     /*
     timer_hw->dbgpause = 0;
     gpio_init(27);