Diff: NewTextLCD.cpp

Revision:

0:3c32eeb9292a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/NewTextLCD.cpp	Thu Sep 22 15:59:17 2011 +0000
@@ -0,0 +1,186 @@
+/* mbed TextLCD Library, for a 4-bit LCD based on HD44780
+ * Copyright (c) 2007-2010, sford, http://mbed.org
+ * Changes by Erik Kerger
+ *
+ *
+ * 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 "NewTextLCD.h"
+#include "mbed.h"
+
+TextLCD::TextLCD(PinName rs, PinName rw, PinName e, PinName d4, PinName d5,
+                 PinName d6, PinName d7, LCDType type) : _rs(rs), _rw(rw), _e(e), 
+                    _d(d4, d5, d6, d7), _type(type) {
+    _rs = 0;            // command mode
+    _rw = 0;            // r/w in defined state
+    _e  = 0;            // 0 --> inactive (most important change to original TextLCD)
+    
+    if (_type != LCDuser)
+        setLCDparam(_type); // otherwise rows, colums, comdelay, adresses must be set before
+
+    wait(0.050f);       // Wait 50ms to ensure powered up
+
+    // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus)
+    // this sets controler into 8 bit mode, so we have a defined state
+    for (int i=0; i<3; i++) {
+        _e = 1;
+        __nop();
+        __nop();
+        _d = 0x3;
+        __nop();        // data setup time at least 60 ns
+        _e = 0;
+        wait(0.005f);   // 5ms
+       }
+    _e = 1;
+    __nop();
+    __nop();
+    _d = 0x2;           // 4 Bit mode (after this command, we have to send 2 nibbles)
+    __nop(); 
+    _e = 0;
+    wait_us(LCDparam.delay);
+    
+    writeCommand(0x28); // Function set 4 Bit, 2Line, 5*7
+    writeCommand(0x08); // Display off
+    cls();              // clear display, reset _column and _row
+    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 = 0x80 | (LCDparam.adresses[row & 3] + column);
+    writeCommand(a);    // set cursor address
+    writeData(c);       // write char
+}
+
+void TextLCD::cls() {
+    writeCommand(0x01); // cls, and set cursor to 0
+    locate(0, 0);       // set internal position
+    wait_us(45 * LCDparam.delay);   // CLS need much time
+}
+
+void TextLCD::locate(int column, int row) {
+    _column = column;   // set position for next char
+    _row = row;         // note: cursor is not set yet
+}
+
+
+
+int TextLCD::_putc(int value) {
+    if (value == '\n') {
+        _column = 0;
+        _row++;
+        if (_row >= LCDparam.rows) {
+            _row = 0;
+        }
+    } else {
+        character(_column, _row, value);
+        _column++;
+        if (_column >= LCDparam.columns) {
+            _column = 0;
+            _row++;
+            if (_row >= LCDparam.rows) {
+                _row = 0;
+            }
+        }
+    }
+    return value;
+}
+
+// Dummy function - read not supported
+int TextLCD::_getc() {
+    return -1;
+}
+
+void TextLCD::writeByte(int value) {
+    _e = 1;
+    __nop();    
+    _d = value >> 4;        // higher nibble first
+    __nop();
+    _e = 0;
+    __nop();
+    __nop();
+    _e = 1;
+    __nop();
+    _d = value >> 0;        // then lower
+    __nop();
+    _e = 0;
+}
+
+void TextLCD::writeCommand(int command) {
+    _rs = 0;
+    writeByte(command);
+    wait_us(LCDparam.delay);
+}
+
+
+void TextLCD::writeData(int data) {
+    _rs = 1;
+    writeByte(data);
+    wait_us(LCDparam.delay);
+}
+
+
+// set user defined char 
+void  TextLCD::writeCGRAM(int address, int pattern[8]){
+    int i;
+    address = address & 7;  //max 8 char
+    for(i=0;i<8;i++){
+        writeCommand(0x40 | (address * 8) + i);
+        writeData(pattern[i]);
+        }
+}   
+
+void TextLCD::setLCDparam(LCDType _type){
+    switch (_type) {
+    
+        case LCD16x2:
+        case LCD16x2B:
+            LCDparam.columns = 16;
+            break;
+        case LCD20x2:
+        case LCD20x4:
+            LCDparam.columns = 20;
+            break;
+        case LCD24x2:
+            LCDparam.columns = 24;
+            break;
+    }
+    if (_type == LCD20x4) 
+        LCDparam.rows = 4;
+    else 
+        LCDparam.rows = 2;
+        
+    LCDparam.adresses[0] = 0;
+    
+    if (_type == LCD16x2B)
+        LCDparam.adresses[1] = 40;
+    else
+        LCDparam.adresses[1] = 0x40;
+        
+    if (_type == LCD20x4) {
+        LCDparam.adresses[2] = 0x14;
+        LCDparam.adresses[3] = 0x54;}
+    else {
+        LCDparam.adresses[2] = 0;
+        LCDparam.adresses[3] = 0;}
+        
+    LCDparam.delay = 50;            // 50 us delays as default              
+}
+