oscar simons / Mbed OS elec350courcework

elec 350 courcework by oscar simons

Dependencies:   BMP280

Fork of Task617-mbedos by University of Plymouth - Stages 1, 2 and 3

TextLCD.cpp@8:eb72f789f912, 2018-01-09 (annotated)

Committer:
jkfadsjk
Date:
Tue Jan 09 19:38:56 2018 +0000
Revision:
8:eb72f789f912
Oscar Simons courcework;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jkfadsjk 8:eb72f789f912 1 /* mbed TextLCD Library, for a 4-bit LCD based on HD44780
jkfadsjk 8:eb72f789f912 2 * Copyright (c) 2007-2010, sford, http://mbed.org
jkfadsjk 8:eb72f789f912 3 *
jkfadsjk 8:eb72f789f912 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
jkfadsjk 8:eb72f789f912 5 * of this software and associated documentation files (the "Software"), to deal
jkfadsjk 8:eb72f789f912 6 * in the Software without restriction, including without limitation the rights
jkfadsjk 8:eb72f789f912 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
jkfadsjk 8:eb72f789f912 8 * copies of the Software, and to permit persons to whom the Software is
jkfadsjk 8:eb72f789f912 9 * furnished to do so, subject to the following conditions:
jkfadsjk 8:eb72f789f912 10 *
jkfadsjk 8:eb72f789f912 11 * The above copyright notice and this permission notice shall be included in
jkfadsjk 8:eb72f789f912 12 * all copies or substantial portions of the Software.
jkfadsjk 8:eb72f789f912 13 *
jkfadsjk 8:eb72f789f912 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
jkfadsjk 8:eb72f789f912 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
jkfadsjk 8:eb72f789f912 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
jkfadsjk 8:eb72f789f912 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
jkfadsjk 8:eb72f789f912 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
jkfadsjk 8:eb72f789f912 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
jkfadsjk 8:eb72f789f912 20 * THE SOFTWARE.
jkfadsjk 8:eb72f789f912 21 */
jkfadsjk 8:eb72f789f912 22
jkfadsjk 8:eb72f789f912 23 #include "TextLCD.h"
jkfadsjk 8:eb72f789f912 24 #include "mbed.h"
jkfadsjk 8:eb72f789f912 25
jkfadsjk 8:eb72f789f912 26 TextLCD::TextLCD(PinName rs, PinName e, PinName d4, PinName d5,
jkfadsjk 8:eb72f789f912 27 PinName d6, PinName d7, LCDType type) : _rs(rs),
jkfadsjk 8:eb72f789f912 28 _e(e), _d(d4, d5, d6, d7),
jkfadsjk 8:eb72f789f912 29 _type(type) {
jkfadsjk 8:eb72f789f912 30
jkfadsjk 8:eb72f789f912 31 _e = 1;
jkfadsjk 8:eb72f789f912 32 _rs = 0; // command mode
jkfadsjk 8:eb72f789f912 33
jkfadsjk 8:eb72f789f912 34 wait(0.015); // Wait 15ms to ensure powered up
jkfadsjk 8:eb72f789f912 35
jkfadsjk 8:eb72f789f912 36 // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus)
jkfadsjk 8:eb72f789f912 37 for (int i=0; i<3; i++) {
jkfadsjk 8:eb72f789f912 38 writeByte(0x3);
jkfadsjk 8:eb72f789f912 39 wait(0.00164); // this command takes 1.64ms, so wait for it
jkfadsjk 8:eb72f789f912 40 }
jkfadsjk 8:eb72f789f912 41 writeByte(0x2); // 4-bit mode
jkfadsjk 8:eb72f789f912 42 wait(0.000040f); // most instructions take 40us
jkfadsjk 8:eb72f789f912 43
jkfadsjk 8:eb72f789f912 44 writeCommand(0x28); // Function set 001 BW N F - -
jkfadsjk 8:eb72f789f912 45 writeCommand(0x0C);
jkfadsjk 8:eb72f789f912 46 writeCommand(0x6); // Cursor Direction and Display Shift : 0000 01 CD S (CD 0-left, 1-right S(hift) 0-no, 1-yes
jkfadsjk 8:eb72f789f912 47 cls();
jkfadsjk 8:eb72f789f912 48 }
jkfadsjk 8:eb72f789f912 49
jkfadsjk 8:eb72f789f912 50 void TextLCD::character(int column, int row, int c) {
jkfadsjk 8:eb72f789f912 51 int a = address(column, row);
jkfadsjk 8:eb72f789f912 52 writeCommand(a);
jkfadsjk 8:eb72f789f912 53 writeData(c);
jkfadsjk 8:eb72f789f912 54 }
jkfadsjk 8:eb72f789f912 55
jkfadsjk 8:eb72f789f912 56 void TextLCD::cls() {
jkfadsjk 8:eb72f789f912 57 writeCommand(0x01); // cls, and set cursor to 0
jkfadsjk 8:eb72f789f912 58 wait(0.00164f); // This command takes 1.64 ms
jkfadsjk 8:eb72f789f912 59 locate(0, 0);
jkfadsjk 8:eb72f789f912 60 }
jkfadsjk 8:eb72f789f912 61
jkfadsjk 8:eb72f789f912 62 void TextLCD::locate(int column, int row) {
jkfadsjk 8:eb72f789f912 63 _column = column;
jkfadsjk 8:eb72f789f912 64 _row = row;
jkfadsjk 8:eb72f789f912 65 }
jkfadsjk 8:eb72f789f912 66
jkfadsjk 8:eb72f789f912 67 int TextLCD::_putc(int value) {
jkfadsjk 8:eb72f789f912 68 if (value == '\n') {
jkfadsjk 8:eb72f789f912 69 _column = 0;
jkfadsjk 8:eb72f789f912 70 _row++;
jkfadsjk 8:eb72f789f912 71 if (_row >= rows()) {
jkfadsjk 8:eb72f789f912 72 _row = 0;
jkfadsjk 8:eb72f789f912 73 }
jkfadsjk 8:eb72f789f912 74 } else {
jkfadsjk 8:eb72f789f912 75 character(_column, _row, value);
jkfadsjk 8:eb72f789f912 76 _column++;
jkfadsjk 8:eb72f789f912 77 if (_column >= columns()) {
jkfadsjk 8:eb72f789f912 78 _column = 0;
jkfadsjk 8:eb72f789f912 79 _row++;
jkfadsjk 8:eb72f789f912 80 if (_row >= rows()) {
jkfadsjk 8:eb72f789f912 81 _row = 0;
jkfadsjk 8:eb72f789f912 82 }
jkfadsjk 8:eb72f789f912 83 }
jkfadsjk 8:eb72f789f912 84 }
jkfadsjk 8:eb72f789f912 85 return value;
jkfadsjk 8:eb72f789f912 86 }
jkfadsjk 8:eb72f789f912 87
jkfadsjk 8:eb72f789f912 88 int TextLCD::_getc() {
jkfadsjk 8:eb72f789f912 89 return -1;
jkfadsjk 8:eb72f789f912 90 }
jkfadsjk 8:eb72f789f912 91
jkfadsjk 8:eb72f789f912 92 void TextLCD::writeByte(int value) {
jkfadsjk 8:eb72f789f912 93 _d = value >> 4;
jkfadsjk 8:eb72f789f912 94 wait(0.000040f); // most instructions take 40us
jkfadsjk 8:eb72f789f912 95 _e = 0;
jkfadsjk 8:eb72f789f912 96 wait(0.000040f);
jkfadsjk 8:eb72f789f912 97 _e = 1;
jkfadsjk 8:eb72f789f912 98 _d = value >> 0;
jkfadsjk 8:eb72f789f912 99 wait(0.000040f);
jkfadsjk 8:eb72f789f912 100 _e = 0;
jkfadsjk 8:eb72f789f912 101 wait(0.000040f); // most instructions take 40us
jkfadsjk 8:eb72f789f912 102 _e = 1;
jkfadsjk 8:eb72f789f912 103 }
jkfadsjk 8:eb72f789f912 104
jkfadsjk 8:eb72f789f912 105 void TextLCD::writeCommand(int command) {
jkfadsjk 8:eb72f789f912 106 _rs = 0;
jkfadsjk 8:eb72f789f912 107 writeByte(command);
jkfadsjk 8:eb72f789f912 108 }
jkfadsjk 8:eb72f789f912 109
jkfadsjk 8:eb72f789f912 110 void TextLCD::writeData(int data) {
jkfadsjk 8:eb72f789f912 111 _rs = 1;
jkfadsjk 8:eb72f789f912 112 writeByte(data);
jkfadsjk 8:eb72f789f912 113 }
jkfadsjk 8:eb72f789f912 114
jkfadsjk 8:eb72f789f912 115 int TextLCD::address(int column, int row) {
jkfadsjk 8:eb72f789f912 116 switch (_type) {
jkfadsjk 8:eb72f789f912 117 case LCD20x4:
jkfadsjk 8:eb72f789f912 118 switch (row) {
jkfadsjk 8:eb72f789f912 119 case 0:
jkfadsjk 8:eb72f789f912 120 return 0x80 + column;
jkfadsjk 8:eb72f789f912 121 case 1:
jkfadsjk 8:eb72f789f912 122 return 0xc0 + column;
jkfadsjk 8:eb72f789f912 123 case 2:
jkfadsjk 8:eb72f789f912 124 return 0x94 + column;
jkfadsjk 8:eb72f789f912 125 case 3:
jkfadsjk 8:eb72f789f912 126 return 0xd4 + column;
jkfadsjk 8:eb72f789f912 127 }
jkfadsjk 8:eb72f789f912 128 case LCD16x2B:
jkfadsjk 8:eb72f789f912 129 return 0x80 + (row * 40) + column;
jkfadsjk 8:eb72f789f912 130 case LCD16x2:
jkfadsjk 8:eb72f789f912 131 case LCD20x2:
jkfadsjk 8:eb72f789f912 132 default:
jkfadsjk 8:eb72f789f912 133 return 0x80 + (row * 0x40) + column;
jkfadsjk 8:eb72f789f912 134 }
jkfadsjk 8:eb72f789f912 135 }
jkfadsjk 8:eb72f789f912 136
jkfadsjk 8:eb72f789f912 137 int TextLCD::columns() {
jkfadsjk 8:eb72f789f912 138 switch (_type) {
jkfadsjk 8:eb72f789f912 139 case LCD20x4:
jkfadsjk 8:eb72f789f912 140 case LCD20x2:
jkfadsjk 8:eb72f789f912 141 return 20;
jkfadsjk 8:eb72f789f912 142 case LCD16x2:
jkfadsjk 8:eb72f789f912 143 case LCD16x2B:
jkfadsjk 8:eb72f789f912 144 default:
jkfadsjk 8:eb72f789f912 145 return 16;
jkfadsjk 8:eb72f789f912 146 }
jkfadsjk 8:eb72f789f912 147 }
jkfadsjk 8:eb72f789f912 148
jkfadsjk 8:eb72f789f912 149 int TextLCD::rows() {
jkfadsjk 8:eb72f789f912 150 switch (_type) {
jkfadsjk 8:eb72f789f912 151 case LCD20x4:
jkfadsjk 8:eb72f789f912 152 return 4;
jkfadsjk 8:eb72f789f912 153 case LCD16x2:
jkfadsjk 8:eb72f789f912 154 case LCD16x2B:
jkfadsjk 8:eb72f789f912 155 case LCD20x2:
jkfadsjk 8:eb72f789f912 156 default:
jkfadsjk 8:eb72f789f912 157 return 2;
jkfadsjk 8:eb72f789f912 158 }
jkfadsjk 8:eb72f789f912 159 }