AconcaguaSci

D13 pin can be use as  digital output pin. D13 pin can be use as i nput pin  together with  external pull-up  and  pull-down resistor . It is not recommand to use the  D13 internal pull-up  resistor because instead of the regular 5V, the voltage will be hanging around 1.7V. Most of Arduino newbies have their first code to blink the LED with D13 pin as an output pin. This really give us big confident to know the code can be successfully executed on the microcontroller. However, due to the build-in D13 pin on different Arduino board has slightly different circuit design,  is there any limitation to use the D13 GPIO pin as input pin ? Let’s find out more! Experiment condition I investigate both the value of D13 digital input and LED light status with the following code with  Arduino Uno Rev3 . and  Arduino nano 3.0.  void setup() { pinMode(13, INPUT); Serial.begin(9600); } void loop() ...