Revision 0:006bcd28cc39, committed 2012-03-21

Comitter:

intrinseca

Date:

Wed Mar 21 23:55:03 2012 +0000

Commit message:

Changed in this revision

diff -r 000000000000 -r 006bcd28cc39 TextLCD.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextLCD.cpp	Wed Mar 21 23:55:03 2012 +0000
@@ -0,0 +1,226 @@
+/* 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.
+ */
+
+#include "TextLCD.h"
+#include "mbed.h"
+
+TextLCD::TextLCD(PinName rs, PinName rw, PinName e, PinName d0, PinName d1,
+                 PinName d2, PinName d3, LCDType type) : _rs(rs), _rw(rw),
+        _e(e), _d(d0, d1, d2, d3), _type(type) {
+    _rs = 0;            // command mode
+    _rw = 0;
+    _e  = 0;            
+    _d.output();        // data out
+
+    wait(0.05);        // Wait 50ms to ensure powered up
+
+    // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus)
+    for (int i=0; i<3; i++) {
+        _e = 1;
+        __nop();
+        _d = 0x3;
+        __nop();
+        _e = 0;
+        wait(0.004f); // 4ms
+       }
+    _e = 1;
+    __nop();
+    _d = 0x2;           // 4 Bit mode
+    __nop(); 
+    _e = 0;
+    
+    writeCommand(0x28); // Function set 4 Bit, 2Line, 5*7
+    writeCommand(0x08); // Display off
+    writeCommand(0x01); // clear Display
+    writeCommand(0x04); // cursor right, Display is not shifted
+    writeCommand(0x0C); // Display on , Cursor off 
+}
+
+void TextLCD::character(int column, int row, int c) {
+    int a = address(column, row);
+    writeCommand(a);
+    writeData(c);
+}
+
+void TextLCD::cls() {
+    writeCommand(0x01); // cls, and set cursor to 0
+    locate(0, 0);
+}
+
+void TextLCD::locate(int column, int row) {
+    _column = column;
+    _row = row;
+}
+
+
+
+int TextLCD::_putc(int value) {
+    if (value == '\n') {
+        _column = 0;
+        _row++;
+        if (_row >= rows()) {
+            _row = 0;
+        }
+    } else {
+        character(_column, _row, value);
+        _column++;
+        if (_column >= columns()) {
+            _column = 0;
+            _row++;
+            if (_row >= rows()) {
+                _row = 0;
+            }
+        }
+    }
+    return value;
+}
+
+int TextLCD::_getc() {
+    int a = address(_column, _row);
+    writeCommand(a);
+    return (readData());
+}
+
+void TextLCD::writeByte(int value) {
+    _e = 1;
+    __nop();    
+    _d = value >> 4;
+    __nop();
+    _e = 0;
+    __nop();
+    _e = 1;
+    __nop();
+    _d = value >> 0;
+    __nop();
+    _e = 0;
+}
+
+void TextLCD::writeCommand(int command) {
+    waitBusy();  // check if display is ready 
+    _rs = 0;
+    writeByte(command);
+}
+
+int TextLCD::readData(){
+    int input;
+    waitBusy();
+    _rw = 1;
+    _rs = 1;
+    __nop();
+    _d.input();  // switch Data port to input
+    _e = 1;
+    __nop();
+    input = _d.read() << 4; // high nibble
+    _e = 0;
+    __nop();
+    _e = 1;
+    __nop();
+    input = input | _d.read(); // low nibble
+    _e = 0;   
+    return (input);
+}
+
+ void TextLCD::waitBusy(){
+    int input;
+    _rw = 1;
+    _rs = 0;
+    __nop();
+    _d.input();      // switch Data port to input
+    do{ 
+        _e = 1;
+        __nop();
+        input = _d.read();              
+        _e = 0;
+        __nop();
+        _e = 1;
+        __nop();
+        _e = 0;
+       }while((0x8 & input) == 0x8);  // wait until display is ready
+    _rw = 0;
+    _d.output();      // switch port back to output  
+ }
+
+void TextLCD::writeData(int data) {
+    waitBusy();
+    _rs = 1;
+    writeByte(data);
+}
+
+
+// set user defined char 
+void  TextLCD::writeCGRAM(int address, int pattern[8]){
+    int i;
+    address = address & 0x07;  //max 8 char
+    for(i=0;i<8;i++){
+        waitBusy();  // check if display is ready 
+        _rs = 0;
+        writeByte(0x40 + address * 8 + i);
+        writeData(pattern[i]);
+        }
+}   
+        
+
+int TextLCD::address(int column, int row) {
+    switch (_type) {
+        case LCD20x4:
+            switch (row) {
+                case 0:
+                    return 0x80 + column;
+                case 1:
+                    return 0xc0 + column;
+                case 2:
+                    return 0x94 + column;
+                case 3:
+                    return 0xd4 + column;
+            }
+        case LCD16x2B:
+            return 0x80 + (row * 40) + column;
+        case LCD16x2:
+        case LCD20x2:
+        default:
+            return 0x80 + (row * 0x40) + column;
+    }
+}
+
+int TextLCD::columns() {
+    switch (_type) {
+        case LCD20x4:
+        case LCD20x2:
+            return 20;
+        case LCD16x2:
+        case LCD16x2B:
+        default:
+            return 16;
+    }
+}
+
+int TextLCD::rows() {
+    switch (_type) {
+        case LCD20x4:
+            return 4;
+        case LCD16x2:
+        case LCD16x2B:
+        case LCD20x2:
+        default:
+            return 2;
+    }
+}

diff -r 000000000000 -r 006bcd28cc39 TextLCD.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextLCD.h	Wed Mar 21 23:55:03 2012 +0000
@@ -0,0 +1,153 @@
+/* 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, _rw, _e;
+    BusInOut _d;
+    LCDType _type;
+
+    int _column;
+    int _row;
+};
+
+#endif