Modified TextLCD lib. The RW signal is also connected to a IO pin. This enable to read out the display memory and the busy flag. The timing is switched from delays to wait for the busy flag. Added writeCGRAM function to define user chars 0-7.

Fork of TextLCD by Peter Drescher

TextLCD.h

Committer:
dreschpe
Date:
2010-12-06
Revision:
3:8582013914a0
Parent:
2:e8326f05cdcb

File content as of revision 3:8582013914a0:

/* mbed TextLCD Library, for a 4-bit LCD based on HD44780
 * Copyright (c) 2007-2010, sford, http://mbed.org
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#ifndef MBED_TEXTLCD_H
#define MBED_TEXTLCD_H

#include "mbed.h"

/** A TextLCD interface for driving 4-bit HD44780-based LCDs
 *
 * Currently supports 16x2, 20x2 and 20x4 panels
 *
 * @code
 * #include "mbed.h"
 * #include "TextLCD.h"
 * 
 * TextLCD lcd(p10, p12, ,p13, p15, p16, p29, p30); // rs, rw, e, d0-d3
 * 
 * int main() {
 *     lcd.printf("Hello mbed\n");
 *
 * //define user chars
 *  int pattern[8];
 *  int pattern1[8];
 *  pattern[0] = 1;              //     *
 *  pattern[1] = 3;              //    **
 *  pattern[2] = 5;              //   * *
 *  pattern[3] = 9;              //  *  *
 *  pattern[4] = 0x11;           // *   *     
 *  pattern[5] = 0x19;           // **  * 
 *  pattern[6] = 0x1d;           // *** *
 *  pattern[7] = 0x1f;           // *****
 *  
 *  pattern1[0] = 0x10;          // *
 *  pattern1[1] = 0x18;          // **
 *  pattern1[2] = 0x14;          // * *
 *  pattern1[3] = 0x12;          // *  *
 *  pattern1[4] = 0x11;          // *   *
 *  pattern1[5] = 0x13;          // *  **
 *  pattern1[6] = 0x17;          // * ***
 *  pattern1[7] = 0x1f;          // *****
 * 
 *  lcd.writeCGRAM(0, pattern);
 *  lcd.writeCGRAM(1, pattern1);
 *  
 *  lcd.locate(15,0);
 *  lcd.putc(0);   // user pattern 0
 *  lcd.putc(1);   // user pattern 1   
 * }
 * @endcode
 */
class TextLCD : public Stream {
public:

    /** LCD panel format */
    enum LCDType {
        LCD16x2     /**< 16x2 LCD panel (default) */
        , LCD16x2B  /**< 16x2 LCD panel alternate addressing */
        , LCD20x2   /**< 20x2 LCD panel */
        , LCD20x4   /**< 20x4 LCD panel */
    };

    /** Create a TextLCD interface
     *
     * @param rs    Instruction/data control line
     * @param e     Enable line (clock)
     * @param rw    read / write
     * @param d0-d3 Data lines
     * @param type  Sets the panel size/addressing mode (default = LCD16x2)
     */
    TextLCD(PinName rs, PinName rw, PinName e, PinName d0, PinName d1, PinName d2, PinName d3, LCDType type = LCD16x2);

#if DOXYGEN_ONLY
    /** Write a character to the LCD
     *
     * @param c The character to write to the display
     */
    int putc(int c);

    /** Write a formated string to the LCD
     *
     * @param format A printf-style format string, followed by the
     *               variables to use in formating the string.
     */
    int printf(const char* format, ...);
#endif

    /** Locate to a screen column and row
     *
     * @param column  The horizontal position from the left, indexed from 0
     * @param row     The vertical position from the top, indexed from 0
     */
    void locate(int column, int row);

    /** Clear the screen and locate to 0,0 */
    void cls();

    int rows();
    int columns();
    
    /** write a user defined char
     *
     * @param address  The user defined char (0-7)
     * @param pattern[8] bit pattern 5*8 of char
     */ 
    void writeCGRAM(int address, int pattern[8]);
    
    /** Get the char at the current position
     * 
     * int getc() 
     */
    
protected:

    // Stream implementation functions
    virtual int _putc(int value);
    virtual int _getc();

    int address(int column, int row);
    void character(int column, int row, int c);
    void writeByte(int value);
    void writeCommand(int command);
    void writeData(int data);
    int readData();
    void waitBusy();
    DigitalOut _rs, _e, _rw;
    BusInOut _d;
    LCDType _type;

    int _column;
    int _row;
};

#endif