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  *
00032  * @code
00033  * #include "mbed.h"
00034  * #include "TextLCD.h"
00035  * 
00036  * TextLCD lcd(p10, p12, ,p13, p15, p16, p29, p30); // rs, rw, e, d0-d3
00037  * 
00038  * int main() {
00039  *     lcd.printf("Hello mbed\n");
00040  *
00041  * //define user chars
00042  *  int pattern[8];
00043  *  int pattern1[8];
00044  *  pattern[0] = 1;              //     *
00045  *  pattern[1] = 3;              //    **
00046  *  pattern[2] = 5;              //   * *
00047  *  pattern[3] = 9;              //  *  *
00048  *  pattern[4] = 0x11;           // *   *     
00049  *  pattern[5] = 0x19;           // **  * 
00050  *  pattern[6] = 0x1d;           // *** *
00051  *  pattern[7] = 0x1f;           // *****
00052  *  
00053  *  pattern1[0] = 0x10;          // *
00054  *  pattern1[1] = 0x18;          // **
00055  *  pattern1[2] = 0x14;          // * *
00056  *  pattern1[3] = 0x12;          // *  *
00057  *  pattern1[4] = 0x11;          // *   *
00058  *  pattern1[5] = 0x13;          // *  **
00059  *  pattern1[6] = 0x17;          // * ***
00060  *  pattern1[7] = 0x1f;          // *****
00061  * 
00062  *  lcd.writeCGRAM(0, pattern);
00063  *  lcd.writeCGRAM(1, pattern1);
00064  *  
00065  *  lcd.locate(15,0);
00066  *  lcd.putc(0);   // user pattern 0
00067  *  lcd.putc(1);   // user pattern 1   
00068  * }
00069  * @endcode
00070  */
00071 class TextLCD : public Stream {
00072 public:
00073  
00074     /** LCD panel format */
00075     enum LCDType {
00076         LCD16x2     /**< 16x2 LCD panel (default) */
00077         , LCD16x2B  /**< 16x2 LCD panel alternate addressing */
00078         , LCD20x2   /**< 20x2 LCD panel */
00079         , LCD20x4   /**< 20x4 LCD panel */
00080     };
00081  
00082     /** Create a TextLCD interface
00083      *
00084      * @param rs    Instruction/data control line
00085      * @param e     Enable line (clock)
00086      * @param rw    read / write
00087      * @param d0-d3 Data lines
00088      * @param type  Sets the panel size/addressing mode (default = LCD16x2)
00089      */
00090     TextLCD(PinName rs, PinName rw, PinName e, PinName d0, PinName d1, PinName d2, PinName d3, LCDType type = LCD16x2);
00091  
00092 #if DOXYGEN_ONLY
00093     /** Write a character to the LCD
00094      *
00095      * @param c The character to write to the display
00096      */
00097     int putc(int c);
00098  
00099     /** Write a formated string to the LCD
00100      *
00101      * @param format A printf-style format string, followed by the
00102      *               variables to use in formating the string.
00103      */
00104     int printf(const char* format, ...);
00105 #endif
00106  
00107     /** Locate to a screen column and row
00108      *
00109      * @param column  The horizontal position from the left, indexed from 0
00110      * @param row     The vertical position from the top, indexed from 0
00111      */
00112     void locate(int column, int row);
00113  
00114     /** Clear the screen and locate to 0,0 */
00115     void cls();
00116  
00117     int rows();
00118     int columns();
00119     
00120     /** write a user defined char
00121      *
00122      * @param address  The user defined char (0-7)
00123      * @param pattern[8] bit pattern 5*8 of char
00124      */ 
00125     void writeCGRAM(int address, int pattern[8]);
00126     
00127     /** Get the char at the current position
00128      * 
00129      * int getc() 
00130      */
00131     
00132 protected:
00133  
00134     // Stream implementation functions
00135     virtual int _putc(int value);
00136     virtual int _getc();
00137  
00138     int address(int column, int row);
00139     void character(int column, int row, int c);
00140     void writeByte(int value);
00141     void writeCommand(int command);
00142     void writeData(int data);
00143     int readData();
00144     void waitBusy();
00145     DigitalOut _rs, _e, _rw;
00146     BusInOut _d;
00147     LCDType _type;
00148  
00149     int _column;
00150     int _row;
00151 };
00152  
00153 #endif
00154