Overview

This project introduces how to send a message from the GR-COTTON board using a USB cable.


Preparation

You will need GR-COTTON and a USB cable (Micro B type).

Make sure the white jumper on the reverse side of GR-COTTON is moved to the “3V3 USB” side. If it is set to the BATT side, remove and reinsert it into the USB side.


Hello World

GR-COTTON uses a USB cable to send a message to your computer. The sample below demonstrates how to display a repetitive “Hello World” message.

Try changing “Hello World” to something else.


#include <arduino.h>

void setup() {
  Serial.begin(9600);
}
 
void loop() {
  Serial.println("Hello World");
  delay(500);
}

 

How to Display Messages

This describes messages displayed in a serial monitor.

The figures below show where to click on KurumiWriter and IDE for GR, respectively.

(Kurumi Writer)

(IDE for GR)



Send a Message Indicating Temperature

GR-COTTON is equipped with an MCU featuring a built-in temperature sensor.

The program below sends a message indicating the temperature measured by the sensor.


#include <arduino.h>

void setup() {
  Serial.begin(9600);
}
 
void loop() {
  Serial.println(getTemperature(0));
  delay(500);
}

Variable Values

This sketch displays the variable values being used.

The sample displays decimal, hexadecimal and binary, separated by tabs.


#include <arduino.h>

void setup() {
  Serial.begin(9600);
}
  
void loop() {
  static int i = 0;
  Serial.print(i); // decimal
  Serial.print("\t"); // tab
  Serial.print(i, HEX); // hex
  Serial.print("\t"); // tab
  Serial.print(i, BIN); // binary
  Serial.println(); // line feed
  i++; 
  delay(100);
}