File content as of revision 0:ef7b6dec773f:

/* mbed TextLCD Library, for a 4-bit LCD based on Optrex DCM20481 NY-LY-ABE
*
* Copyright (c) 2007-2010, sford modified by E.Sjoukes
*
* 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 i
* 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 "OptrexLCD.h"
#include "mbed.h"

// initialiseer  
TextLCD::TextLCD(PinName rs, PinName e, PinName d0, PinName d1, PinName d2, 
            PinName d3, LCDType type) : _rs(rs), _e(e), _d(d0, d1, d2, d3), _type(type) 
{
    _e  = 1;                // enable normaly high
    _rs = 0;                // command mode
 
    wait(0.015);            // Wait 15ms to ensure powered up

    for (int i=0; i<3; i++) // send "Display Settings" 3 times
    {
        writeByte(0x3);
        wait(0.00164);      // this command takes 1.64ms, so wait for it
    }
    writeByte(0x2);         // 4-bit mode
    wait(0.000040f);        // most instructions take 40us

    writeCommand(0x28);     // Function set 001 BW N F - -
    writeCommand(0x0C);
    writeCommand(0x6);      // Cursor Direction and Display Shift : 0000 01 CD S (CD 0-left, 1-right S(hift) 0-no, 1-yes
    cls();
}
 
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
    wait(0.003000f);       // This command takes 3ms with Optrex, normaly it wood be 1.64ms
    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() 
{
     return -1;
}
 
void TextLCD::writeByte(int value) 
{
     _d = value >> 4;
     wait(0.000040f);   // most instructions take 40us
     _e = 0;
     wait(0.000075f);   // enable puls of Optrex needs to be 75us 
     _e = 1;
     _d = value >> 0;
     wait(0.000075f);   // enable puls of Optrex needs to be 75us
     _e = 0;
     wait(0.000075f);   // enable puls of Optrex needs to be 75us
     _e = 1;
}
 
void TextLCD::writeCommand(int command) 
{
     _rs = 0;
     writeByte(command);
}

void TextLCD::writeData(int data) 
{
     _rs = 1;
     writeByte(data);
}

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;
     }
}