Analog I/O

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

Ethernet
Servo Motor
Stepping Motor
Character LCD
SPI
I²C (Wire)
SD Card
SD (File Operations)
Periodic Operation
Clock (RTC)
PPG (Pulse Generator)
WiFiEsp
ICS (Serial Servo)

Overview
Task
Queue
Timer
Interrupt Management

This library is to input/output an analog signal.

analogReference

Description

Configures the reference voltage used for analog input (i.e. the value used as the top of the input range).

Syntax

analogReference(uint8_t mode)

Parameters

mode:
DEFAULT: 3.3V
INTERNAL: 1.1V (internal voltage)
EXTERNAL: AVREF pin supply voltage

Returns

None

analogRead

Description

Reads the value from the specified analog pin.

Syntax

int analogRead(uint8_t analog_pin)

Parameters

analog_pin: The number of the analog input pin to read from A0(14) to A5(19) and A6(10) to A9(13)

Returns

0 to 4095

analogWrite

Description

Writes an analog value (PWM wave) to a pin. Can be used to light an LED at varying brightnesses or drive a motor at various speeds. The frequency of the PWM signal is approximately 490Hz.

Syntax

analogWrite(uint8_t pin, int value);

Parameters

pin: The number of the pin
value: The duty cycle of the output PWM (0 - 255).

Returns

None

analogWriteDAC

Description

Outputs digital values which it first converts to analog. Unlike analogWrite, it does not output a PWM signal. 3.3V are output when the digital value is 4095.

Syntax

analogWriteDAC(int pin, int value)

Parameters

pin: The number of the pin to write to (24 only)
value: Analog converted value (0 - 4095).

Returns

None

analogWriteFrequency

Description

Change the frequency of PWM from the default of 490Hz. The pins 3, 7, 9, 10, and 13 can be changed.

Syntax

analogWriteFrequency(uint32_t freq);

Parameters

freq: Frequency

Returns

None

The LED on the GR-ROSE board lights up smoothly.

#include <Arduino.h>
void setup(){
}
  
void loop(){
    for(int i = 0; i < 256; i++){
        analogWrite(PIN_LED1, i);
        delay(3);
    }
    for(int i = 0; i < 256; i++){
        analogWrite(PIN_LED1, 256 - i - 1);
        delay(3);
    }
}