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Dependents: TextLCD_SR4_TestProgram ServoInterfaceBoardExample1
Revision 2:e768257aba09, committed 2010-10-25
- Comitter:
- shintamainjp
- Date:
- Mon Oct 25 22:41:56 2010 +0000
- Parent:
- 1:7c375c1ac22c
- Commit message:
Changed in this revision
--- /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;
+ }
+}
--- /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
--- 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++);
- }
-}
--- 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