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 #ifndef MBED_TEXTLCD_H
00024 #define MBED_TEXTLCD_H
00025 
00026 #include "mbed.h"
00027 
00028 /** A TextLCD interface for driving 4-bit HD44780-based LCDs
00029  *
00030  * Currently supports 16x2, 20x2 and 20x4 panels
00031  * added support for 16x1 panels (Th. Lunzer 11-05-24)
00032  *
00033  * @code
00034  * #include "mbed.h"
00035  * #include "TextLCD.h"
00036  * 
00037  * TextLCD lcd(p10, p12, p15, p16, p29, p30); // rs, e, d0-d3
00038  * 
00039  * int main() {
00040  *     lcd.printf("Hello World!\n");
00041  * }
00042  * @endcode
00043  */
00044 class TextLCD : public Stream {
00045 public:
00046 
00047     /** LCD panel format */
00048     enum LCDType {
00049         LCD16x2     /**< 16x2 LCD panel (default) */
00050         , LCD16x2B  /**< 16x2 LCD panel alternate addressing */
00051         , LCD20x2   /**< 20x2 LCD panel */
00052         , LCD20x4   /**< 20x4 LCD panel */
00053         , LCD16x1   /**< 16x1 LCD panel */
00054     };
00055 
00056     /** Create a TextLCD interface
00057      *
00058      * @param rs    Instruction/data control line
00059      * @param e     Enable line (clock)
00060      * @param d0-d3 Data lines
00061      * @param type  Sets the panel size/addressing mode (default = LCD16x2)
00062      */
00063     TextLCD(PinName rs, PinName e, PinName d0, PinName d1, PinName d2, PinName d3, LCDType type = LCD16x2);
00064 
00065 #if DOXYGEN_ONLY
00066     /** Write a character to the LCD
00067      *
00068      * @param c The character to write to the display
00069      */
00070     int putc(int c);
00071 
00072     /** Write a formated string to the LCD
00073      *
00074      * @param format A printf-style format string, followed by the
00075      *               variables to use in formating the string.
00076      */
00077     int printf(const char* format, ...);
00078 #endif
00079 
00080     /** Locate to a screen column and row
00081      *
00082      * @param column  The horizontal position from the left, indexed from 0
00083      * @param row     The vertical position from the top, indexed from 0
00084      */
00085     void locate(int column, int row);
00086 
00087     /** Clear the screen and locate to 0,0 */
00088     void cls();
00089 
00090     int rows();
00091     int columns();
00092 
00093 protected:
00094 
00095     // Stream implementation functions
00096     virtual int _putc(int value);
00097     virtual int _getc();
00098 
00099     int address(int column, int row);
00100     void character(int column, int row, int c);
00101     void writeByte(int value);
00102     void writeCommand(int command);
00103     void writeData(int data);
00104 
00105     DigitalOut _rs, _e;
00106     BusOut _d;
00107     LCDType _type;
00108 
00109     int _column;
00110     int _row;
00111 };
00112 
00113 #endif