Floating pins are bad and you should prevent them by using either a pull down resistor or a pull up resistor. This type of pin is called a floating pin and will basically return random values based on how much electrical interference is present around it. That pin is neither grounded (pulled low) or exposed to voltage (pulled high). Imagine you’ve got a pin setup as an input, and connected to a switch that is off. It’s worth noting that zero can also be represented in code by the words false or low, and 1 can be represented by the values true or high.īut using the correct voltage is only half the battle. 8 and 2.4 and you won’t reliably be able to predict the pin reading. 8 volts) it will return 0, and when it is exposed to a voltage over 2.4 volts it will return high. When a pin on the nodemcu is connected to ground (or a voltage under. A digital input pin will give a value of either 0 or 1 when the digitalRead(pin) function is called. The first major pin mode we’re going to look at is the digital input. Today we’re going to use the nodeMCU version of the ESP8266 and ESP32 because they happen to be my favorite and are readily available on amazon, but there are hundreds of board variants based on these two chips. Your specific project needs will determine the best microcontroller for your project. Not every pin can do every job, and each microcontroller has a specific number of pins that are able to be used with each pin type.

Microcontrollers have 4 major pin modes in the Arduino IDE, digital inputs, digital outputs, analog inputs, and analog outputs. Today on the hookup we’re going to learn how to pick the right microcontroller for your project by examining the different pin modes available on the ESP8266 and the ESP32 based nodemcus. Pin Modes on the NodeMCU ESP32 and ESP8266

Esp32 vs esp8266