diff --git a/basic/basic.c b/basic/basic.c
index 0ec319b..fd015f2 100644
--- a/basic/basic.c
+++ b/basic/basic.c
@@ -109,7 +109,8 @@ void rbInit() {
     gpioSetPullup (&RB_BUSINT_IO, gpioPullupMode_PullUp);
     gpioSetInterrupt(RB_BUSINT, gpioInterruptSense_Edge, gpioInterruptEdge_Single, gpioInterruptEvent_ActiveLow);
     gpioIntEnable(RB_BUSINT);
-    //add this to catch interrupt:
+    // 1. remove PIOINT3_IRQHandler from gpio/gpio.c
+    // 2. add this to catch interrupt:
     /*
 	void PIOINT3_IRQHandler(void) {    
 	    if (gpioIntStatus(RB_BUSINT)) {