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So now let’s perform a simple example to connect a push button with any GPIO pin and turn on an LED connected to another digital pin. As shown in the above pinout, we will be using GPIO15 to connect the push button and GPIO22 to connect a push button.
A button in this un-pressed state (with a valid pull-down resister) will yield an input reading of 0 (LOW). Then when the button is pushed down, the voltage will flow from the 3.3V pin into the INPUT GPIO pin (whilst continuing through the 1kOhm resister) to give us a reading of 1 (HIGH).
Which is true when the GPIO presses the button?
Your current code jumps from (Button=Down, Light=On) to (Button=Down, Light=Off) and back again. My code here is untested, and I’m not completely sure which way the GPIO.input () goes when the button is pressed and released. I assume it’s 0/False most of the time and 1/True when the button is pressed.
What is the name of the push button pin?
In code first 2 lines give a name to input pin 15 as PushButton and output pin 22 as LEDPIN. So now inside the code, we can use these name instead of pin numbers. In setup () function, we use pinMode () function to initialize PushButton pin as an INPUT and LEDPIN as an INPUT.
Why do you use GPIO pins with ESP32?
When you use push button with ESP32, we have to use GPIO pins as digital input pins. Because we will read the state of the push button. The push button will give two logical states either high or low.
The 1kOhm resister is simply used to dampen the voltage going from the 3.3V pin directly into the GPIO pin when the button is pressed. The 10kOhm resister plays a much more important role and is known as a “pull-down” resistor.
How does a GPIO function work on a Raspberry Pi?
A GPIO event in the Raspberry Pi Python GPIO library works by calling a Python function whenever an event is triggered. Such a function is called a callback function.