Basic Library

Digital I/O
Analog I/O
Advanced I/O
Time
Math
Trigonometry
Random Numbers
Bits and Bytes
Interrupts
Serial Comm.

Standard Library

Camera
Servo Motor
Stepping Motor
Character LCD
SPI
I2C (Wire)
SD Card
SD (File Operations)
Periodic Operation
Clock (RTC)

Mbed Tips

Overview
Storage
Wi-Fi
TLS (HTTPS)
Audio
Microphone
BLE

Digital I/O

This GR-LYCHEE library is for configuring the digital signal (HIGH/LOW) to function as either input or output.

pinMode

Description
Configures the specified pin to behave either as an input or an output.
Syntax
pinMode(pin, mode)
Parameters
pin: The number of the pin to set
mode: INPUT or OUTPUT
Returns
None

digitalWrite

Description
Write a HIGH or a LOW value to a digital pin.
Syntax
digitalWrite(uint8_t pin, uint8_t value)
Parameters
pin: The pin number
value: HIGH or LOW
Returns
None

digitalRead

Description
Reads the value from a specified digital pin, either HIGH or LOW.
Syntax
digitalRead(uint8_t pin)
Parameters
pin: The pin number
Returns
HIGH or LOW

Sample Program

Sample for digitalWrite and digitalRead.


#include <Arduino.h>
#define INTERVAL 100
    
void setup()
{
    pinMode(PIN_LED_RED   , OUTPUT);
    pinMode(PIN_LED_GREEN , OUTPUT);
    pinMode(PIN_SW0        , INPUT);
}
    
void loop()
{
    if(digitalRead(PIN_SW0)){
        digitalWrite(PIN_LED_GREEN, HIGH);
    } else {
        digitalWrite(PIN_LED_GREEN, LOW);
    }
    digitalWrite(PIN_LED_RED, HIGH);
    delay(INTERVAL);
    digitalWrite(PIN_LED_RED, LOW);
    delay(INTERVAL);
}