Shinichiro Nakamura
http://mbed.org/users/shintamainjp/notebook/textlcd_sr4_en/
Dependents: TextLCD_SR4_TestProgram ServoInterfaceBoardExample1
TextLCD_SR4.cpp@2:e768257aba09, 2010-10-25 (annotated)
- Committer:
- shintamainjp
- Date:
- Mon Oct 25 22:41:56 2010 +0000
- Revision:
- 2:e768257aba09
- Parent:
- 0:580f94424a91
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| shintamainjp | 0:580f94424a91 | 1 | /* mbed TextLCD_SR4 Library, for a 4-bit LCD based on HD44780 |
| shintamainjp | 0:580f94424a91 | 2 | * Copyright (c) 2007-2010, sford |
| shintamainjp | 0:580f94424a91 | 3 | * |
| shintamainjp | 0:580f94424a91 | 4 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| shintamainjp | 0:580f94424a91 | 5 | * of this software and associated documentation files (the "Software"), to deal |
| shintamainjp | 0:580f94424a91 | 6 | * in the Software without restriction, including without limitation the rights |
| shintamainjp | 0:580f94424a91 | 7 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| shintamainjp | 0:580f94424a91 | 8 | * copies of the Software, and to permit persons to whom the Software is |
| shintamainjp | 0:580f94424a91 | 9 | * furnished to do so, subject to the following conditions: |
| shintamainjp | 0:580f94424a91 | 10 | * |
| shintamainjp | 0:580f94424a91 | 11 | * The above copyright notice and this permission notice shall be included in |
| shintamainjp | 0:580f94424a91 | 12 | * all copies or substantial portions of the Software. |
| shintamainjp | 0:580f94424a91 | 13 | * |
| shintamainjp | 0:580f94424a91 | 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| shintamainjp | 0:580f94424a91 | 15 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| shintamainjp | 0:580f94424a91 | 16 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| shintamainjp | 0:580f94424a91 | 17 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| shintamainjp | 0:580f94424a91 | 18 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| shintamainjp | 0:580f94424a91 | 19 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| shintamainjp | 0:580f94424a91 | 20 | * THE SOFTWARE. |
| shintamainjp | 0:580f94424a91 | 21 | */ |
| shintamainjp | 0:580f94424a91 | 22 | |
| shintamainjp | 0:580f94424a91 | 23 | /* |
| shintamainjp | 0:580f94424a91 | 24 | * Modified for http://mbed.org/users/shintamainjp/notebook/textlcd_sr4_en/ |
| shintamainjp | 0:580f94424a91 | 25 | * Shinichiro Nakamura |
| shintamainjp | 0:580f94424a91 | 26 | */ |
| shintamainjp | 0:580f94424a91 | 27 | |
| shintamainjp | 0:580f94424a91 | 28 | #include "TextLCD_SR4.h" |
| shintamainjp | 0:580f94424a91 | 29 | #include "mbed.h" |
| shintamainjp | 0:580f94424a91 | 30 | |
| shintamainjp | 0:580f94424a91 | 31 | TextLCD_SR4::TextLCD_SR4(PinName rs, PinName e, PinName dat, PinName clk, LCDType type) |
| shintamainjp | 0:580f94424a91 | 32 | : _rs(rs), _e(e), _dat(dat), _clk(clk), _type(type) { |
| shintamainjp | 0:580f94424a91 | 33 | |
| shintamainjp | 0:580f94424a91 | 34 | _e = 1; |
| shintamainjp | 0:580f94424a91 | 35 | _rs = 0; // command mode |
| shintamainjp | 0:580f94424a91 | 36 | |
| shintamainjp | 0:580f94424a91 | 37 | wait(0.015); // Wait 15ms to ensure powered up |
| shintamainjp | 0:580f94424a91 | 38 | |
| shintamainjp | 0:580f94424a91 | 39 | // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus) |
| shintamainjp | 0:580f94424a91 | 40 | for (int i = 0; i < 3; i++) { |
| shintamainjp | 0:580f94424a91 | 41 | writeByte(0x3); |
| shintamainjp | 0:580f94424a91 | 42 | wait(0.00164); // this command takes 1.64ms, so wait for it |
| shintamainjp | 0:580f94424a91 | 43 | } |
| shintamainjp | 0:580f94424a91 | 44 | writeByte(0x2); // 4-bit mode |
| shintamainjp | 0:580f94424a91 | 45 | wait(0.000040f); // most instructions take 40us |
| shintamainjp | 0:580f94424a91 | 46 | |
| shintamainjp | 0:580f94424a91 | 47 | writeCommand(0x28); // Function set 001 BW N F - - |
| shintamainjp | 0:580f94424a91 | 48 | writeCommand(0x0C); |
| shintamainjp | 0:580f94424a91 | 49 | writeCommand(0x6); // Cursor Direction and Display Shift : 0000 01 CD S (CD 0-left, 1-right S(hift) 0-no, 1-yes |
| shintamainjp | 0:580f94424a91 | 50 | cls(); |
| shintamainjp | 0:580f94424a91 | 51 | } |
| shintamainjp | 0:580f94424a91 | 52 | |
| shintamainjp | 0:580f94424a91 | 53 | void TextLCD_SR4::character(int column, int row, int c) { |
| shintamainjp | 0:580f94424a91 | 54 | int a = address(column, row); |
| shintamainjp | 0:580f94424a91 | 55 | writeCommand(a); |
| shintamainjp | 0:580f94424a91 | 56 | writeData(c); |
| shintamainjp | 0:580f94424a91 | 57 | } |
| shintamainjp | 0:580f94424a91 | 58 | |
| shintamainjp | 0:580f94424a91 | 59 | void TextLCD_SR4::cls() { |
| shintamainjp | 0:580f94424a91 | 60 | writeCommand(0x01); // cls, and set cursor to 0 |
| shintamainjp | 0:580f94424a91 | 61 | wait(0.00164f); // This command takes 1.64 ms |
| shintamainjp | 0:580f94424a91 | 62 | locate(0, 0); |
| shintamainjp | 0:580f94424a91 | 63 | } |
| shintamainjp | 0:580f94424a91 | 64 | |
| shintamainjp | 0:580f94424a91 | 65 | void TextLCD_SR4::locate(int column, int row) { |
| shintamainjp | 0:580f94424a91 | 66 | _column = column; |
| shintamainjp | 0:580f94424a91 | 67 | _row = row; |
| shintamainjp | 0:580f94424a91 | 68 | } |
| shintamainjp | 0:580f94424a91 | 69 | |
| shintamainjp | 0:580f94424a91 | 70 | int TextLCD_SR4::_putc(int value) { |
| shintamainjp | 0:580f94424a91 | 71 | if (value == '\n') { |
| shintamainjp | 0:580f94424a91 | 72 | _column = 0; |
| shintamainjp | 0:580f94424a91 | 73 | _row++; |
| shintamainjp | 0:580f94424a91 | 74 | if (_row >= rows()) { |
| shintamainjp | 0:580f94424a91 | 75 | _row = 0; |
| shintamainjp | 0:580f94424a91 | 76 | } |
| shintamainjp | 0:580f94424a91 | 77 | } else { |
| shintamainjp | 0:580f94424a91 | 78 | character(_column, _row, value); |
| shintamainjp | 0:580f94424a91 | 79 | _column++; |
| shintamainjp | 0:580f94424a91 | 80 | if (_column >= columns()) { |
| shintamainjp | 0:580f94424a91 | 81 | _column = 0; |
| shintamainjp | 0:580f94424a91 | 82 | _row++; |
| shintamainjp | 0:580f94424a91 | 83 | if (_row >= rows()) { |
| shintamainjp | 0:580f94424a91 | 84 | _row = 0; |
| shintamainjp | 0:580f94424a91 | 85 | } |
| shintamainjp | 0:580f94424a91 | 86 | } |
| shintamainjp | 0:580f94424a91 | 87 | } |
| shintamainjp | 0:580f94424a91 | 88 | return value; |
| shintamainjp | 0:580f94424a91 | 89 | } |
| shintamainjp | 0:580f94424a91 | 90 | |
| shintamainjp | 0:580f94424a91 | 91 | int TextLCD_SR4::_getc() { |
| shintamainjp | 0:580f94424a91 | 92 | return -1; |
| shintamainjp | 0:580f94424a91 | 93 | } |
| shintamainjp | 0:580f94424a91 | 94 | |
| shintamainjp | 0:580f94424a91 | 95 | void TextLCD_SR4::writeByte(int value) { |
| shintamainjp | 0:580f94424a91 | 96 | writeToShiftRegister(value << 0); |
| shintamainjp | 0:580f94424a91 | 97 | wait(0.000040f); // most instructions take 40us |
| shintamainjp | 0:580f94424a91 | 98 | _e = 0; |
| shintamainjp | 0:580f94424a91 | 99 | wait(0.000040f); |
| shintamainjp | 0:580f94424a91 | 100 | _e = 1; |
| shintamainjp | 0:580f94424a91 | 101 | writeToShiftRegister(value << 4); |
| shintamainjp | 0:580f94424a91 | 102 | wait(0.000040f); |
| shintamainjp | 0:580f94424a91 | 103 | _e = 0; |
| shintamainjp | 0:580f94424a91 | 104 | wait(0.000040f); // most instructions take 40us |
| shintamainjp | 0:580f94424a91 | 105 | _e = 1; |
| shintamainjp | 0:580f94424a91 | 106 | } |
| shintamainjp | 0:580f94424a91 | 107 | |
| shintamainjp | 0:580f94424a91 | 108 | void TextLCD_SR4::writeToShiftRegister(int value) { |
| shintamainjp | 0:580f94424a91 | 109 | /* |
| shintamainjp | 0:580f94424a91 | 110 | * MSB first. |
| shintamainjp | 0:580f94424a91 | 111 | */ |
| shintamainjp | 0:580f94424a91 | 112 | for (int i = 0; i < 8; i++) { |
| shintamainjp | 0:580f94424a91 | 113 | if (value & (1 << (7 - i))) { |
| shintamainjp | 0:580f94424a91 | 114 | _dat = 1; |
| shintamainjp | 0:580f94424a91 | 115 | } else { |
| shintamainjp | 0:580f94424a91 | 116 | _dat = 0; |
| shintamainjp | 0:580f94424a91 | 117 | } |
| shintamainjp | 0:580f94424a91 | 118 | _clk = 1; |
| shintamainjp | 0:580f94424a91 | 119 | wait_us(1); |
| shintamainjp | 0:580f94424a91 | 120 | _clk = 0; |
| shintamainjp | 0:580f94424a91 | 121 | wait_us(1); |
| shintamainjp | 0:580f94424a91 | 122 | } |
| shintamainjp | 0:580f94424a91 | 123 | } |
| shintamainjp | 0:580f94424a91 | 124 | |
| shintamainjp | 0:580f94424a91 | 125 | void TextLCD_SR4::writeCommand(int command) { |
| shintamainjp | 0:580f94424a91 | 126 | _rs = 0; |
| shintamainjp | 0:580f94424a91 | 127 | writeByte(command); |
| shintamainjp | 0:580f94424a91 | 128 | } |
| shintamainjp | 0:580f94424a91 | 129 | |
| shintamainjp | 0:580f94424a91 | 130 | void TextLCD_SR4::writeData(int data) { |
| shintamainjp | 0:580f94424a91 | 131 | _rs = 1; |
| shintamainjp | 0:580f94424a91 | 132 | writeByte(data); |
| shintamainjp | 0:580f94424a91 | 133 | } |
| shintamainjp | 0:580f94424a91 | 134 | |
| shintamainjp | 0:580f94424a91 | 135 | int TextLCD_SR4::address(int column, int row) { |
| shintamainjp | 0:580f94424a91 | 136 | switch (_type) { |
| shintamainjp | 0:580f94424a91 | 137 | case LCD20x4: |
| shintamainjp | 0:580f94424a91 | 138 | switch (row) { |
| shintamainjp | 0:580f94424a91 | 139 | case 0: |
| shintamainjp | 0:580f94424a91 | 140 | return 0x80 + column; |
| shintamainjp | 0:580f94424a91 | 141 | case 1: |
| shintamainjp | 0:580f94424a91 | 142 | return 0xc0 + column; |
| shintamainjp | 0:580f94424a91 | 143 | case 2: |
| shintamainjp | 0:580f94424a91 | 144 | return 0x94 + column; |
| shintamainjp | 0:580f94424a91 | 145 | case 3: |
| shintamainjp | 0:580f94424a91 | 146 | return 0xd4 + column; |
| shintamainjp | 0:580f94424a91 | 147 | } |
| shintamainjp | 0:580f94424a91 | 148 | case LCD16x2B: |
| shintamainjp | 0:580f94424a91 | 149 | return 0x80 + (row * 40) + column; |
| shintamainjp | 0:580f94424a91 | 150 | case LCD16x2: |
| shintamainjp | 0:580f94424a91 | 151 | case LCD20x2: |
| shintamainjp | 0:580f94424a91 | 152 | default: |
| shintamainjp | 0:580f94424a91 | 153 | return 0x80 + (row * 0x40) + column; |
| shintamainjp | 0:580f94424a91 | 154 | } |
| shintamainjp | 0:580f94424a91 | 155 | } |
| shintamainjp | 0:580f94424a91 | 156 | |
| shintamainjp | 0:580f94424a91 | 157 | int TextLCD_SR4::columns() { |
| shintamainjp | 0:580f94424a91 | 158 | switch (_type) { |
| shintamainjp | 0:580f94424a91 | 159 | case LCD20x4: |
| shintamainjp | 0:580f94424a91 | 160 | case LCD20x2: |
| shintamainjp | 0:580f94424a91 | 161 | return 20; |
| shintamainjp | 0:580f94424a91 | 162 | case LCD16x2: |
| shintamainjp | 0:580f94424a91 | 163 | case LCD16x2B: |
| shintamainjp | 0:580f94424a91 | 164 | default: |
| shintamainjp | 0:580f94424a91 | 165 | return 16; |
| shintamainjp | 0:580f94424a91 | 166 | } |
| shintamainjp | 0:580f94424a91 | 167 | } |
| shintamainjp | 0:580f94424a91 | 168 | |
| shintamainjp | 0:580f94424a91 | 169 | int TextLCD_SR4::rows() { |
| shintamainjp | 0:580f94424a91 | 170 | switch (_type) { |
| shintamainjp | 0:580f94424a91 | 171 | case LCD20x4: |
| shintamainjp | 0:580f94424a91 | 172 | return 4; |
| shintamainjp | 0:580f94424a91 | 173 | case LCD16x2: |
| shintamainjp | 0:580f94424a91 | 174 | case LCD16x2B: |
| shintamainjp | 0:580f94424a91 | 175 | case LCD20x2: |
| shintamainjp | 0:580f94424a91 | 176 | default: |
| shintamainjp | 0:580f94424a91 | 177 | return 2; |
| shintamainjp | 0:580f94424a91 | 178 | } |
| shintamainjp | 0:580f94424a91 | 179 | } |