TextLCD_With_40x2 - Alpha numeric LCD Library with support for 40x2 d…

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Tony Beck / Mbed 2 deprecated TextLCD_With_40x2

Alpha numeric LCD Library with support for 40x2 display

TextLCD.cpp@0:7e92a1d71370, 2010-06-12 (annotated)

Committer:: tonydbeck
Date:: Sat Jun 12 01:17:02 2010 +0000
Revision:: 0:7e92a1d71370

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User	Revision	Line number	New contents of line
tonydbeck	0:7e92a1d71370	1	/* mbed TextLCD Library, for a 4-bit LCD based on HD44780
tonydbeck	0:7e92a1d71370	2	* Copyright (c) 2007-2010, sford
tonydbeck	0:7e92a1d71370	3	*
tonydbeck	0:7e92a1d71370	4	* Permission is hereby granted, free of charge, to any person obtaining a copy
tonydbeck	0:7e92a1d71370	5	* of this software and associated documentation files (the "Software"), to deal
tonydbeck	0:7e92a1d71370	6	* in the Software without restriction, including without limitation the rights
tonydbeck	0:7e92a1d71370	7	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
tonydbeck	0:7e92a1d71370	8	* copies of the Software, and to permit persons to whom the Software is
tonydbeck	0:7e92a1d71370	9	* furnished to do so, subject to the following conditions:
tonydbeck	0:7e92a1d71370	10	*
tonydbeck	0:7e92a1d71370	11	* The above copyright notice and this permission notice shall be included in
tonydbeck	0:7e92a1d71370	12	* all copies or substantial portions of the Software.
tonydbeck	0:7e92a1d71370	13	*
tonydbeck	0:7e92a1d71370	14	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
tonydbeck	0:7e92a1d71370	15	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
tonydbeck	0:7e92a1d71370	16	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
tonydbeck	0:7e92a1d71370	17	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
tonydbeck	0:7e92a1d71370	18	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
tonydbeck	0:7e92a1d71370	19	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
tonydbeck	0:7e92a1d71370	20	* THE SOFTWARE.
tonydbeck	0:7e92a1d71370	21	*/
tonydbeck	0:7e92a1d71370	22
tonydbeck	0:7e92a1d71370	23	#include "TextLCD.h"
tonydbeck	0:7e92a1d71370	24	#include "mbed.h"
tonydbeck	0:7e92a1d71370	25
tonydbeck	0:7e92a1d71370	26	TextLCD::TextLCD(PinName rs, PinName e, PinName d0, PinName d1,
tonydbeck	0:7e92a1d71370	27	PinName d2, PinName d3, LCDType type) : _rs(rs),
tonydbeck	0:7e92a1d71370	28	_e(e), _d(d0, d1, d2, d3),
tonydbeck	0:7e92a1d71370	29	_type(type) {
tonydbeck	0:7e92a1d71370	30
tonydbeck	0:7e92a1d71370	31	_e = 1;
tonydbeck	0:7e92a1d71370	32	_rs = 0; // command mode
tonydbeck	0:7e92a1d71370	33
tonydbeck	0:7e92a1d71370	34	wait(0.015); // Wait 15ms to ensure powered up
tonydbeck	0:7e92a1d71370	35
tonydbeck	0:7e92a1d71370	36	// send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus)
tonydbeck	0:7e92a1d71370	37	for (int i=0; i<3; i++) {
tonydbeck	0:7e92a1d71370	38	writeByte(0x3);
tonydbeck	0:7e92a1d71370	39	wait(0.00164); // this command takes 1.64ms, so wait for it
tonydbeck	0:7e92a1d71370	40	}
tonydbeck	0:7e92a1d71370	41	writeByte(0x2); // 4-bit mode
tonydbeck	0:7e92a1d71370	42	wait(0.000040f); // most instructions take 40us
tonydbeck	0:7e92a1d71370	43
tonydbeck	0:7e92a1d71370	44	writeCommand(0x28); // Function set 001 BW N F - -
tonydbeck	0:7e92a1d71370	45	writeCommand(0x0C);
tonydbeck	0:7e92a1d71370	46	writeCommand(0x6); // Cursor Direction and Display Shift : 0000 01 CD S (CD 0-left, 1-right S(hift) 0-no, 1-yes
tonydbeck	0:7e92a1d71370	47	cls();
tonydbeck	0:7e92a1d71370	48	}
tonydbeck	0:7e92a1d71370	49
tonydbeck	0:7e92a1d71370	50	void TextLCD::character(int column, int row, int c) {
tonydbeck	0:7e92a1d71370	51	int a = address(column, row);
tonydbeck	0:7e92a1d71370	52	writeCommand(a);
tonydbeck	0:7e92a1d71370	53	writeData(c);
tonydbeck	0:7e92a1d71370	54	}
tonydbeck	0:7e92a1d71370	55
tonydbeck	0:7e92a1d71370	56	void TextLCD::cls() {
tonydbeck	0:7e92a1d71370	57	writeCommand(0x01); // cls, and set cursor to 0
tonydbeck	0:7e92a1d71370	58	wait(0.00164f); // This command takes 1.64 ms
tonydbeck	0:7e92a1d71370	59	locate(0, 0);
tonydbeck	0:7e92a1d71370	60	}
tonydbeck	0:7e92a1d71370	61
tonydbeck	0:7e92a1d71370	62	void TextLCD::locate(int column, int row) {
tonydbeck	0:7e92a1d71370	63	_column = column;
tonydbeck	0:7e92a1d71370	64	_row = row;
tonydbeck	0:7e92a1d71370	65	}
tonydbeck	0:7e92a1d71370	66
tonydbeck	0:7e92a1d71370	67	int TextLCD::_putc(int value) {
tonydbeck	0:7e92a1d71370	68	if (value == '\n') {
tonydbeck	0:7e92a1d71370	69	_column = 0;
tonydbeck	0:7e92a1d71370	70	_row++;
tonydbeck	0:7e92a1d71370	71	if (_row >= rows()) {
tonydbeck	0:7e92a1d71370	72	_row = 0;
tonydbeck	0:7e92a1d71370	73	}
tonydbeck	0:7e92a1d71370	74	} else {
tonydbeck	0:7e92a1d71370	75	character(_column, _row, value);
tonydbeck	0:7e92a1d71370	76	_column++;
tonydbeck	0:7e92a1d71370	77	if (_column >= columns()) {
tonydbeck	0:7e92a1d71370	78	_column = 0;
tonydbeck	0:7e92a1d71370	79	_row++;
tonydbeck	0:7e92a1d71370	80	if (_row >= rows()) {
tonydbeck	0:7e92a1d71370	81	_row = 0;
tonydbeck	0:7e92a1d71370	82	}
tonydbeck	0:7e92a1d71370	83	}
tonydbeck	0:7e92a1d71370	84	}
tonydbeck	0:7e92a1d71370	85	return value;
tonydbeck	0:7e92a1d71370	86	}
tonydbeck	0:7e92a1d71370	87
tonydbeck	0:7e92a1d71370	88	int TextLCD::_getc() {
tonydbeck	0:7e92a1d71370	89	return -1;
tonydbeck	0:7e92a1d71370	90	}
tonydbeck	0:7e92a1d71370	91
tonydbeck	0:7e92a1d71370	92	void TextLCD::writeByte(int value) {
tonydbeck	0:7e92a1d71370	93	_d = value >> 4;
tonydbeck	0:7e92a1d71370	94	wait(0.000040f); // most instructions take 40us
tonydbeck	0:7e92a1d71370	95	_e = 0;
tonydbeck	0:7e92a1d71370	96	wait(0.000040f);
tonydbeck	0:7e92a1d71370	97	_e = 1;
tonydbeck	0:7e92a1d71370	98	_d = value >> 0;
tonydbeck	0:7e92a1d71370	99	wait(0.000040f);
tonydbeck	0:7e92a1d71370	100	_e = 0;
tonydbeck	0:7e92a1d71370	101	wait(0.000040f); // most instructions take 40us
tonydbeck	0:7e92a1d71370	102	_e = 1;
tonydbeck	0:7e92a1d71370	103	}
tonydbeck	0:7e92a1d71370	104
tonydbeck	0:7e92a1d71370	105	void TextLCD::writeCommand(int command) {
tonydbeck	0:7e92a1d71370	106	_rs = 0;
tonydbeck	0:7e92a1d71370	107	writeByte(command);
tonydbeck	0:7e92a1d71370	108	}
tonydbeck	0:7e92a1d71370	109
tonydbeck	0:7e92a1d71370	110	void TextLCD::writeData(int data) {
tonydbeck	0:7e92a1d71370	111	_rs = 1;
tonydbeck	0:7e92a1d71370	112	writeByte(data);
tonydbeck	0:7e92a1d71370	113	}
tonydbeck	0:7e92a1d71370	114
tonydbeck	0:7e92a1d71370	115	int TextLCD::address(int column, int row) {
tonydbeck	0:7e92a1d71370	116	switch (_type) {
tonydbeck	0:7e92a1d71370	117	case LCD20x4:
tonydbeck	0:7e92a1d71370	118	switch (row) {
tonydbeck	0:7e92a1d71370	119	case 0:
tonydbeck	0:7e92a1d71370	120	return 0x80 + column;
tonydbeck	0:7e92a1d71370	121	case 1:
tonydbeck	0:7e92a1d71370	122	return 0xc0 + column;
tonydbeck	0:7e92a1d71370	123	case 2:
tonydbeck	0:7e92a1d71370	124	return 0x94 + column;
tonydbeck	0:7e92a1d71370	125	case 3:
tonydbeck	0:7e92a1d71370	126	return 0xd4 + column;
tonydbeck	0:7e92a1d71370	127	}
tonydbeck	0:7e92a1d71370	128	case LCD16x2B:
tonydbeck	0:7e92a1d71370	129	return 0x80 + (row * 40) + column;
tonydbeck	0:7e92a1d71370	130	case LCD16x2:
tonydbeck	0:7e92a1d71370	131	case LCD20x2:
tonydbeck	0:7e92a1d71370	132	default:
tonydbeck	0:7e92a1d71370	133	return 0x80 + (row * 0x40) + column;
tonydbeck	0:7e92a1d71370	134	case LCD40x2:
tonydbeck	0:7e92a1d71370	135	switch (row) {
tonydbeck	0:7e92a1d71370	136	case 0:
tonydbeck	0:7e92a1d71370	137	return 0x80 + column;
tonydbeck	0:7e92a1d71370	138	case 1:
tonydbeck	0:7e92a1d71370	139	return 0xc0 +column;
tonydbeck	0:7e92a1d71370	140	}
tonydbeck	0:7e92a1d71370	141	}
tonydbeck	0:7e92a1d71370	142	}
tonydbeck	0:7e92a1d71370	143
tonydbeck	0:7e92a1d71370	144	int TextLCD::columns() {
tonydbeck	0:7e92a1d71370	145	switch (_type) {
tonydbeck	0:7e92a1d71370	146	case LCD20x4:
tonydbeck	0:7e92a1d71370	147	case LCD20x2:
tonydbeck	0:7e92a1d71370	148	return 20;
tonydbeck	0:7e92a1d71370	149	case LCD16x2:
tonydbeck	0:7e92a1d71370	150	case LCD16x2B:
tonydbeck	0:7e92a1d71370	151	default:
tonydbeck	0:7e92a1d71370	152	return 16;
tonydbeck	0:7e92a1d71370	153	case LCD40x2:
tonydbeck	0:7e92a1d71370	154	return 40;
tonydbeck	0:7e92a1d71370	155	}
tonydbeck	0:7e92a1d71370	156	}
tonydbeck	0:7e92a1d71370	157
tonydbeck	0:7e92a1d71370	158	int TextLCD::rows() {
tonydbeck	0:7e92a1d71370	159	switch (_type) {
tonydbeck	0:7e92a1d71370	160	case LCD20x4:
tonydbeck	0:7e92a1d71370	161	return 4;
tonydbeck	0:7e92a1d71370	162	case LCD16x2:
tonydbeck	0:7e92a1d71370	163	case LCD16x2B:
tonydbeck	0:7e92a1d71370	164	case LCD20x2:
tonydbeck	0:7e92a1d71370	165	case LCD40x2:
tonydbeck	0:7e92a1d71370	166	default:
tonydbeck	0:7e92a1d71370	167	return 2;
tonydbeck	0:7e92a1d71370	168	}
tonydbeck	0:7e92a1d71370	169	}

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	12 Jun 2010
Imports:	13
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	1
Followers:	2

TextLCD.cpp@0:7e92a1d71370, 2010-06-12 (annotated)

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