TextLCD.h

00001 /* mbed TextLCD Library, for a 4-bit LCD based on HD44780
00002  * Copyright (c) 2007-2010, sford, http://mbed.org
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00020  * THE SOFTWARE.
00021  */
00022 
00023 /*
00024  * Comment: Added support for LCD40x2 and LCD8x2
00025  * Name:    davervw
00026  * Date:    02/26/2011
00027  */
00028 
00029 #ifndef MBED_TEXTLCD_H
00030 #define MBED_TEXTLCD_H
00031 
00032 #include "mbed.h"
00033 
00034 /** A TextLCD interface for driving 4-bit HD44780-based LCDs
00035  *
00036  * Currently supports 16x2, 20x2, 20x4, 40x2, and 8x2 panels
00037  *
00038  * @code
00039  * #include "mbed.h"
00040  * #include "TextLCD.h"
00041  * 
00042  * TextLCD lcd(p10, p12, p15, p16, p29, p30); // rs, e, d4-d7
00043  * 
00044  * int main() {
00045  *     lcd.printf("Hello World!\n");
00046  * }
00047  * @endcode
00048  */
00049 class TextLCD : public Stream {
00050 public:
00051 
00052     /** LCD panel format */
00053     enum LCDType {
00054         LCD16x2     /**< 16x2 LCD panel (default) */
00055         , LCD16x2B  /**< 16x2 LCD panel alternate addressing */
00056         , LCD20x2   /**< 20x2 LCD panel */
00057         , LCD20x4   /**< 20x4 LCD panel */
00058         , LCD40x2   /**< 40x2 LCD panel */
00059         , LCD8x2    /**<  8x2 LCD panel */
00060     };
00061 
00062     /** Create a TextLCD interface
00063      *
00064      * @param rs    Instruction/data control line
00065      * @param e     Enable line (clock)
00066      * @param d4-d7 Data lines for using as a 4-bit interface
00067      * @param type  Sets the panel size/addressing mode (default = LCD16x2)
00068      */
00069     TextLCD(PinName rs, PinName e, PinName d4, PinName d5, PinName d6, PinName d7, LCDType type = LCD16x2);
00070 
00071 #if DOXYGEN_ONLY
00072     /** Write a character to the LCD
00073      *
00074      * @param c The character to write to the display
00075      */
00076     int putc(int c);
00077 
00078     /** Write a formated string to the LCD
00079      *
00080      * @param format A printf-style format string, followed by the
00081      *               variables to use in formating the string.
00082      */
00083     int printf(const char* format, ...);
00084 #endif
00085 
00086     /** Locate to a screen column and row
00087      *
00088      * @param column  The horizontal position from the left, indexed from 0
00089      * @param row     The vertical position from the top, indexed from 0
00090      */
00091     void locate(int column, int row);
00092 
00093     /** Clear the screen and locate to 0,0 */
00094     void cls();
00095 
00096     int rows();
00097     int columns();
00098 
00099 protected:
00100 
00101     // Stream implementation functions
00102     virtual int _putc(int value);
00103     virtual int _getc();
00104 
00105     int address(int column, int row);
00106     void character(int column, int row, int c);
00107     void writeByte(int value);
00108     void writeCommand(int command);
00109     void writeData(int data);
00110 
00111     DigitalOut _rs, _e;
00112     BusOut _d;
00113     LCDType _type;
00114 
00115     int _column;
00116     int _row;
00117 };
00118 
00119 #endif