/* mbed TextLCD Library, for a 4-bit LCD based on HD44780
 * Copyright (c) 2007-2010, sford, http://mbed.org
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "TextLCD.h"

TextLCD::TextLCD(PinName rs, PinName e, PinName d4, PinName d5, PinName d6, PinName d7, LCDType type)
	: _rs(rs), _e(e), _d(d4, d5, d6, d7), _type(type)
{
	_e  = 1;
	_rs = 0;            // command mode

	wait_us(15000);        // Wait 15ms to ensure powered up

	// send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus)
	for (int i=0; i<3; i++) {
		writeByte(0x3);
		wait_us(1640);  // this command takes 1.64ms, so wait for it
	}
	writeByte(0x2);     // 4-bit mode
	wait_us(40);    // most instructions take 40us

	writeCommand(0x28); // Function set 001 BW N F - -
	writeCommand(0x0C);
	writeCommand(0x6);  // Cursor Direction and Display Shift : 0000 01 CD S (CD 0-left, 1-right S(hift) 0-no, 1-yes
	cls();
}

void TextLCD::character(int column, int row, int c)
{
	int a = address(column, row);
	writeCommand(a);
	writeData(c);
}

void TextLCD::cls()
{
	writeCommand(0x01); // cls, and set cursor to 0
	wait_us(1640);     // This command takes 1.64 ms
	locate(0, 0);
}

void TextLCD::locate(int column, int row)
{
	_column = column;
	_row = row;
}

int TextLCD::_putc(int value)
{
	if (value == '\n') {
		_column = 0;
		_row++;
		if (_row >= rows()) {
			_row = 0;
		}
	} else {
		character(_column, _row, value);
		_column++;
		if (_column >= columns()) {
			_column = 0;
			_row++;
			if (_row >= rows()) {
				_row = 0;
			}
		}
	}
	return value;
}

int TextLCD::_getc()
{
	return -1;
}

void TextLCD::writeByte(int value)
{
	_d.write(value >> 4);
	wait_us(40); // most instructions take 40us
	_e = 0;
	wait_us(40);
	_e = 1;
	_d.write(value >> 0);
	wait_us(40);
	_e = 0;
	wait_us(40);  // most instructions take 40us
	_e = 1;
}

void TextLCD::writeCommand(int command)
{
	_rs = 0;
	writeByte(command);
}

void TextLCD::writeData(int data)
{
	_rs = 1;
	writeByte(data);
}

int TextLCD::address(int column, int row)
{
	switch (_type) {
	case LCD20x4:
		switch (row) {
		case 0:
			return 0x80 + column;
		case 1:
			return 0xc0 + column;
		case 2:
			return 0x94 + column;
		case 3:
			return 0xd4 + column;
		}
	case LCD16x2B:
		return 0x80 + (row * 40) + column;
	case LCD16x2:
	case LCD20x2:
	default:
		return 0x80 + (row * 0x40) + column;
	}
}

int TextLCD::columns()
{
	switch (_type) {
	case LCD20x4:
	case LCD20x2:
		return 20;
	case LCD16x2:
	case LCD16x2B:
	default:
		return 16;
	}
}

int TextLCD::rows()
{
	switch (_type) {
	case LCD20x4:
		return 4;
	case LCD16x2:
	case LCD16x2B:
	case LCD20x2:
	default:
		return 2;
	}
}


