http://mbed.org/users/shintamainjp/notebook/textlcd_sr4_en/

Dependents:   TextLCD_SR4_TestProgram ServoInterfaceBoardExample1

Files at this revision

API Documentation at this revision

Comitter:
shintamainjp
Date:
Mon Oct 25 22:41:56 2010 +0000
Parent:
1:7c375c1ac22c
Commit message:

Changed in this revision

TextLCD_SR4.cpp Show annotated file Show diff for this revision Revisions of this file
TextLCD_SR4.h Show annotated file Show diff for this revision Revisions of this file
main.cpp Show diff for this revision Revisions of this file
mbed.bld Show diff for this revision Revisions of this file
diff -r 7c375c1ac22c -r e768257aba09 TextLCD_SR4.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextLCD_SR4.cpp	Mon Oct 25 22:41:56 2010 +0000
@@ -0,0 +1,179 @@
+/* mbed TextLCD_SR4 Library, for a 4-bit LCD based on HD44780
+ * Copyright (c) 2007-2010, sford
+ *
+ * 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.
+ */
+
+/*
+ * Modified for http://mbed.org/users/shintamainjp/notebook/textlcd_sr4_en/
+ * Shinichiro Nakamura
+ */
+
+#include "TextLCD_SR4.h"
+#include "mbed.h"
+
+TextLCD_SR4::TextLCD_SR4(PinName rs, PinName e, PinName dat, PinName clk, LCDType type)
+        : _rs(rs), _e(e), _dat(dat), _clk(clk), _type(type) {
+
+    _e  = 1;
+    _rs = 0;            // command mode
+
+    wait(0.015);        // Wait 15ms 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++) {
+        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_SR4::character(int column, int row, int c) {
+    int a = address(column, row);
+    writeCommand(a);
+    writeData(c);
+}
+
+void TextLCD_SR4::cls() {
+    writeCommand(0x01); // cls, and set cursor to 0
+    wait(0.00164f);     // This command takes 1.64 ms
+    locate(0, 0);
+}
+
+void TextLCD_SR4::locate(int column, int row) {
+    _column = column;
+    _row = row;
+}
+
+int TextLCD_SR4::_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_SR4::_getc() {
+    return -1;
+}
+
+void TextLCD_SR4::writeByte(int value) {
+    writeToShiftRegister(value << 0);
+    wait(0.000040f); // most instructions take 40us
+    _e = 0;
+    wait(0.000040f);
+    _e = 1;
+    writeToShiftRegister(value << 4);
+    wait(0.000040f);
+    _e = 0;
+    wait(0.000040f);  // most instructions take 40us
+    _e = 1;
+}
+
+void TextLCD_SR4::writeToShiftRegister(int value) {
+    /*
+     * MSB first.
+     */
+    for (int i = 0; i < 8; i++) {
+        if (value & (1 << (7 - i))) {
+            _dat = 1;
+        } else {
+            _dat = 0;
+        }
+        _clk = 1;
+        wait_us(1);
+        _clk = 0;
+        wait_us(1);
+    }
+}
+
+void TextLCD_SR4::writeCommand(int command) {
+    _rs = 0;
+    writeByte(command);
+}
+
+void TextLCD_SR4::writeData(int data) {
+    _rs = 1;
+    writeByte(data);
+}
+
+int TextLCD_SR4::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_SR4::columns() {
+    switch (_type) {
+        case LCD20x4:
+        case LCD20x2:
+            return 20;
+        case LCD16x2:
+        case LCD16x2B:
+        default:
+            return 16;
+    }
+}
+
+int TextLCD_SR4::rows() {
+    switch (_type) {
+        case LCD20x4:
+            return 4;
+        case LCD16x2:
+        case LCD16x2B:
+        case LCD20x2:
+        default:
+            return 2;
+    }
+}
diff -r 7c375c1ac22c -r e768257aba09 TextLCD_SR4.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextLCD_SR4.h	Mon Oct 25 22:41:56 2010 +0000
@@ -0,0 +1,96 @@
+
+#ifndef _TEXT_LCD_SR4_H
+#define _TEXT_LCD_SR4_H
+
+#include "mbed.h"
+
+/*
+ * Modified for http://mbed.org/users/shintamainjp/notebook/textlcd_sr4_en/
+ * Shinichiro Nakamura
+ */
+
+/**
+ * A TextLCD_SR4 interface for driving 4-bit HD44780-based LCDs with shift register.
+ *
+ * Currently supports 16x2, 20x2 and 20x4 panels
+ *
+ * @code
+ * #include "mbed.h"
+ * #include "TextLCD_SR4.h"
+ *
+ * TextLCD_SR4 lcd(p29, p30, p28, p27); // rs, e, dat, clk
+ *
+ * int main() {
+ *     lcd.printf("Hello World!\n");
+ * }
+ * @endcode
+ */
+class TextLCD_SR4 : 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_SR4 interface
+     *
+     * @param rs    Instruction/data control line
+     * @param e     Enable line (clock)
+     * @param dat   Data line
+     * @param clk   Clock line
+     */
+    TextLCD_SR4(PinName rs, PinName e, PinName dat, PinName clk, 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();
+
+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);
+
+    void writeToShiftRegister(int value);
+
+    DigitalOut _rs, _e, _dat, _clk;
+    LCDType _type;
+
+    int _column;
+    int _row;
+};
+
+#endif
diff -r 7c375c1ac22c -r e768257aba09 main.cpp
--- a/main.cpp	Mon Oct 25 22:41:04 2010 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,17 +0,0 @@
-#include "mbed.h"
-#include "TextLCD_SR4.h"
-
-TextLCD_SR4 lcd(p29, p30, p28, p27);
-
-int main() {
-    lcd.locate(0, 0);
-    lcd.printf("  TextLCD_SR4   ");
-    lcd.locate(0, 1);
-    lcd.printf("  Library test  ");
-    wait(5);
-    int n = 0;
-    while (1) {
-        lcd.locate(0, 1);
-        lcd.printf("count:%10d", n++);
-    }
-}
diff -r 7c375c1ac22c -r e768257aba09 mbed.bld
--- a/mbed.bld	Mon Oct 25 22:41:04 2010 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +0,0 @@
-http://mbed.org/users/mbed_official/code/mbed/builds/e2ac27c8e93e