Example I2C code on SAMD21 for Martin

gistfile1.txt

// vi:ts=4
// ----------------------------------------------------------------------------
// HelloWorld - simple demonstration of lcd
// Created by Bill Perry 2016-07-02
// bperrybap@opensource.billsworld.billandterrie.com
//
// This example code is unlicensed and is released into the public domain

#include <Wire.h>
#include <hd44780.h>                       // main hd44780 header
#include <hd44780ioClass/hd44780_I2Cexp.h> // i2c expander i/o class header

hd44780_I2Cexp lcd; // declare lcd object: auto locate & auto config expander chip

// LCD geometry
const int LCD_COLS = 16;
const int LCD_ROWS = 2;

void setup()
{
int status;

	status = lcd.begin(LCD_COLS, LCD_ROWS);
	if(status) // non zero status means it was unsuccesful
	{
		// hd44780 has a fatalError() routine that blinks an led if possible
		// begin() failed so blink error code using the onboard LED if possible
		hd44780::fatalError(status); // does not return
	}

	// initalization was successful, the backlight should be on now

	// Print a message to the LCD
	lcd.print("CQ CQ ON4CBK");
  lcd.setCursor(4,2);
  lcd.print("de ON8HZ :-)");

}

void loop() {}