Improved version of Simon Ford's TextDisplay library, with addressing and timing fixes. Supports up to 20x4 text displays.

Files at this revision

API Documentation at this revision

Comitter:
bikeNomad
Date:
Sun Feb 14 00:28:08 2010 +0000
Commit message:

Changed in this revision

Terminal.cpp Show annotated file Show diff for this revision Revisions of this file
Terminal.h Show annotated file Show diff for this revision Revisions of this file
TextDisplay.cpp Show annotated file Show diff for this revision Revisions of this file
TextDisplay.h Show annotated file Show diff for this revision Revisions of this file
TextDisplays.h Show annotated file Show diff for this revision Revisions of this file
TextLCD.cpp Show annotated file Show diff for this revision Revisions of this file
TextLCD.h Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r 2c5bba968d7c Terminal.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Terminal.cpp	Sun Feb 14 00:28:08 2010 +0000
@@ -0,0 +1,73 @@
+/* mbed Terminal TextDisplay Library
+ * Copyright (c) 2007-2009 sford
+ * Released under the MIT License: http://mbed.org/license/mit
+ */
+
+#include "Terminal.h"
+
+#include "mbed.h"
+
+Terminal::Terminal(PinName tx, PinName rx) : _serial(tx, rx) {
+    cls();
+}
+
+void Terminal::character(uint16_t column, uint16_t row, int c) {
+    // Cursor Home    <ESC>[{ROW};{COLUMN}H 
+    _serial.printf("\033[%u;%uH%c", row + 1, column + 1, c);
+}
+
+uint16_t Terminal::columns() {
+    return 80;
+}
+
+uint16_t Terminal::rows() { 
+    return 35; 
+}
+
+void Terminal::cls() {
+    _serial.printf("\033[2J");
+}
+
+void Terminal::foreground(uint32_t colour) {
+
+    /* Set Attribute Mode    <ESC>[{n}m
+     * - Sets display attribute settings. The following lists standard attributes:
+     * 
+     * Foreground Colours
+     * 30    Black
+     * 31    Red
+     * 32    Green
+     * 33    Yellow
+     * 34    Blue
+     * 35    Magenta
+     * 36    Cyan
+     * 37    White
+     */
+    uint32_t r = (colour >> 23) & 1;
+    uint32_t g = (colour >> 15) & 1;
+    uint32_t b = (colour >> 7) & 1;
+    uint32_t bgr = (b << 2) | (g << 1) | (r << 0);
+    uint32_t c = 30 + bgr;
+    _serial.printf("\033[%um", c);
+}
+
+void Terminal::background(uint32_t colour) {
+
+    /* Background Colours
+     * 40    Black
+     * 41    Red
+     * 42    Green
+     * 43    Yellow
+     * 44    Blue
+     * 45    Magenta
+     * 46    Cyan
+     * 47    White
+     */
+    uint32_t r = (colour >> 23) & 1;
+    uint32_t g = (colour >> 15) & 1;
+    uint32_t b = (colour >> 7) & 1;
+    uint32_t bgr = (b << 2) | (g << 1) | (r << 0);
+    uint32_t c = 40 + bgr;
+    _serial.printf("\033[%um", c);
+}
+
diff -r 000000000000 -r 2c5bba968d7c Terminal.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Terminal.h	Sun Feb 14 00:28:08 2010 +0000
@@ -0,0 +1,37 @@
+/* mbed Terminal TextDisplay Library
+ * Copyright (c) 2007-2009 sford
+ * Released under the MIT License: http://mbed.org/license/mit
+ *
+ * Modified by Ned Konz
+ * to add baud rate setting
+ *
+ * Implementation of a TextDisplay using a VT100 Terminal and 
+ * escape codes (e.g. Teraterm, Hyperterminal)
+ */
+
+#include "TextDisplay.h"
+
+#ifndef MBED_TERMINAL_H
+#define MBED_TERMINAL_H
+
+class Terminal : public TextDisplay {
+public:
+
+    Terminal(PinName tx, PinName rx);
+
+    virtual void character(uint16_t column, uint16_t row, int c);
+    virtual uint16_t rows(); 
+    virtual uint16_t columns();  
+
+    virtual void cls();
+    virtual void foreground(uint32_t colour);
+    virtual void background(uint32_t colour);
+    virtual void baud(uint16_t newbaud) { _serial.baud(newbaud); }
+
+protected:
+
+    Serial _serial;
+    
+};
+
+#endif
diff -r 000000000000 -r 2c5bba968d7c TextDisplay.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextDisplay.cpp	Sun Feb 14 00:28:08 2010 +0000
@@ -0,0 +1,57 @@
+/* mbed TextDisplay Display Library Base Class
+ * Copyright (c) 2007-2009 sford
+ * Released under the MIT License: http://mbed.org/license/mit
+ */
+ 
+#include "TextDisplay.h"
+
+TextDisplay::TextDisplay() {
+    _row = 0;
+    _column = 0;
+}
+    
+int TextDisplay::_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;
+}
+
+// crude cls implementation, should generally be overwritten in derived class
+void TextDisplay::cls() {
+    locate(0, 0);
+    for(int i=0; i<columns()*rows(); i++) {
+        putc(' ');
+    }
+}
+
+void TextDisplay::locate(uint16_t column, uint16_t row) {
+    _column = column;
+    _row = row;
+}
+
+int TextDisplay::_getc() {
+    return -1;
+}
+        
+void TextDisplay::foreground(uint32_t colour) {
+    _foreground = colour;
+}
+
+void TextDisplay::background(uint32_t colour) {
+    _background = colour;
+}
diff -r 000000000000 -r 2c5bba968d7c TextDisplay.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextDisplay.h	Sun Feb 14 00:28:08 2010 +0000
@@ -0,0 +1,52 @@
+/* mbed TextDisplay Library Base Class
+ * Copyright (c) 2007-2009 sford
+ * Released under the MIT License: http://mbed.org/license/mit
+ *
+ * A common base class for Text displays
+ * To port a new display, derive from this class and implement
+ * the constructor (setup the display), character (put a character
+ * at a location), rows and columns (number of rows/cols) functions.
+ * Everything else (locate, printf, putc, cls) will come for free
+ *
+ * The model is the display will wrap at the right and bottom, so you can
+ * keep writing and will always get valid characters. The location is 
+ * maintained internally to the class to make this easy
+ */
+
+#ifndef MBED_TEXTDISPLAY_H
+#define MBED_TEXTDISPLAY_H
+
+#include "mbed.h"
+
+class TextDisplay : public Stream {
+public:
+
+    // functions needing implementation in derived implementation class
+    TextDisplay();
+    virtual void character(uint16_t column, uint16_t row, int c) = 0;
+    virtual uint16_t rows() = 0;
+    virtual uint16_t columns() = 0;
+    
+    // functions that come for free, but can be overwritten
+    virtual void cls();
+    virtual void locate(uint16_t column, uint16_t row);
+    virtual void foreground(uint32_t colour);
+    virtual void background(uint32_t colour);
+    // putc (from Stream)
+    // printf (from Stream)
+    
+protected:
+
+    virtual int _putc(int value);
+    virtual int _getc();
+
+    // character location
+    uint16_t _column;
+    uint16_t _row;
+
+    // colours
+    uint32_t _foreground;
+    uint32_t _background;
+};
+
+#endif
diff -r 000000000000 -r 2c5bba968d7c TextDisplays.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextDisplays.h	Sun Feb 14 00:28:08 2010 +0000
@@ -0,0 +1,20 @@
+/* mbed Text Displays Collection Library
+ * Copyright (c) 2007-2009 sford
+ * Released under the MIT License: http://mbed.org/license/mit
+ *
+ * A library for providing a common base class for Text 
+ * displays, to provide commonality and simplify porting of new displays 
+ */
+
+#ifndef MBED_TEXT_DISPLAYS_H
+#define MBED_TEXT_DISPLAYS_H
+
+// Display Base Class
+#include "TextDisplay.h"
+
+// Text Displays
+#include "TextLCD.h"
+#include "Terminal.h"
+
+
+#endif
diff -r 000000000000 -r 2c5bba968d7c TextLCD.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextLCD.cpp	Sun Feb 14 00:28:08 2010 +0000
@@ -0,0 +1,161 @@
+/* mbed TextLCD Library
+ * Copyright (c) 2007-2009 sford
+ * Released under the MIT License: http://mbed.org/license/mit
+ *
+ * Modified by Ned Konz to provide better support for 4-line LCDs and ones with other controller chips.
+ */
+
+#include "TextLCD.h"
+#include "mbed.h"
+
+/*
+ * useful info found at http://www.a-netz.de/lcd.en.php
+ *
+ * Initialisation
+ * ==============
+ *
+ * After attaching the supply voltage/after a reset, the display needs to be brought in to a defined state
+ *
+ * - wait approximately 15 ms so the display is ready to execute commands
+ * - Execute the command 0x30 ("Display Settings") three times (wait 1,64ms after each command, the busy flag cannot be queried now).
+ * - The display is in 8 bit mode, so if you have only connected 4 data pins you should only transmit the higher nibble of each command.
+ * - If you want to use the 4 bit mode, now you can execute the command to switch over to this mode now.
+ * - Execute the "clear display" command
+ *
+ * Timing
+ * ======
+ *
+ * Nearly all commands transmitted to the display need 40us for execution.
+ * Exceptions are the commands "Clear Display and Reset" and "Set Cursor to Start Position"
+ * These commands need 1.64ms for execution. These timings are valid for all displays working with an
+ * internal clock of 250kHz. But I do not know any displays that use other frequencies. Any time you
+ * can use the busy flag to test if the display is ready to accept the next command.
+ *
+ * _e is kept low except when being used.
+ * _rw is kept 0 (write) apart from actions that use it differently
+ * _rs is set by the data/command writes
+ */
+
+TextLCD::TextLCD(PinName rs, PinName rw, PinName e, PinName d0, PinName d1,
+                 PinName d2, PinName d3, uint16_t rows, uint16_t cols) : _rw(rw), _rs(rs),
+        _e(e), _d(d0, d1, d2, d3), _rows(rows), _columns(cols) {
+
+    _rw = 0;
+    wait_us(1);     // min. 100nsec delay
+    _e  = 0;
+    _rs = 0;    // command mode
+    _d.output();
+
+    reset();
+    cls();
+}
+
+void TextLCD::reset() {
+    wait_ms(15);
+    // e is low at this point, as is rw.
+    // 2. Send 0x3 and wait 150 ms (will stay in 8-bit mode if already there)
+    writeHalfByte(0x3);
+    wait_ms(5);
+    // 3. Send 0x3 and wait 150 ms (will go to 8-bit mode if was in 4-bit without any garbage nibble)
+    writeHalfByte(0x3);
+    wait_ms(5);
+    // 4. Send 0x3 and wait 250 ms (will go to 8-bit mode even if garbage nibble was previously received)
+    writeHalfByte(0x3);
+    wait_ms(5);
+    // 5. Send 0x2 and wait 200 ms (should go to 4-bit mode now)
+    writeHalfByte(0x2);
+    wait_ms(5);
+    // 7. Send LCD setup sequence (eg 0x2, 0x8 (=0x28), 0x0, 0x8 (=0x08), etc.)
+    writeCommand(0x28);    // Function set 001 BW N F - -
+    wait_ms(15);
+
+    writeCommand(0x08);     // display off, cursor invisible
+    wait_ms(15);
+
+    writeCommand(0x01);
+    wait_ms(15);      // 1.64ms command
+
+    writeCommand(0x0C);     // display enabled, cursor invisible
+    wait_ms(15);
+
+    writeCommand(0x6);  //  Cursor Direction and Display Shift : 0000 01 CD S (CD 0-left, 1-right S(hift) 0-no, 1-yes
+    wait_ms(15);
+
+    locate(0,0);
+}
+
+// memory starts at 0x80, and is 0x40 chars long per row
+// However, rows 2 and 3 of 4-line displays are actually adjacent to rows 0 and 1.
+// 16x4 displays are addressed the same way as 20x4 ones.
+
+void TextLCD::character(uint16_t column, uint16_t row, int c) {
+    int address;
+    address = 0x80 + ((row & ~2) * 0x40) + column;
+    if (row > 1)
+        address += 20;
+    writeCommand(address);
+    writeData(c);
+}
+
+void TextLCD::writeHalfByte(uint16_t value) {
+    _e = 1;
+    wait_us(1);
+    _d = value & 0x0F;    // send data on bus
+    wait_us(1); // setup time
+    _e = 0; // strobe
+    wait_us(1); // hold time
+}
+
+void TextLCD::writeByte(uint16_t value) {
+    writeHalfByte(value>>4);
+    writeHalfByte(value);
+}
+
+void TextLCD::writeCommand(uint16_t command) {
+    _rs = 0;
+    writeByte(command);
+    waitUntilDone();
+}
+
+void TextLCD::writeData(uint16_t data) {
+    _rs = 1;
+    writeByte(data);
+    waitUntilDone();
+}
+
+void TextLCD::cls() {
+    writeCommand(0x01);
+    wait_us(2000);      // 1.64ms command
+    locate(0,0);
+}
+
+// This should be changed to use readAddressAndBusy() when that works.
+void TextLCD::waitUntilDone() {
+    wait_us(60);
+}
+
+// Return the busy/address byte.
+// The busy flag is the high bit.
+// Not yet working reliably.
+uint16_t TextLCD::readAddressAndBusy() {
+    _d.input();
+    _rw = 1;
+    wait_us(1);
+    _e = 1;
+    wait_us(1);
+    _e = 0;
+
+    uint16_t retval = _d.read() << 4;
+
+    wait_us(1);
+    _e = 1;
+    wait_us(1);
+    _e = 0;
+
+    retval |= _d.read();
+    _rw = 0;
+
+    _d.output();
+    return retval;
+}
+
diff -r 000000000000 -r 2c5bba968d7c TextLCD.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextLCD.h	Sun Feb 14 00:28:08 2010 +0000
@@ -0,0 +1,37 @@
+/* mbed TextLCD Library Base Class
+ * Copyright (c) 2007-2009 sford
+ * Released under the MIT License: http://mbed.org/license/mit
+ * Modified by Ned Konz to provide better support for 4-line LCDs and ones with other controller chips.
+ */
+#include "TextDisplay.h"
+
+#ifndef MBED_TEXTLCD_H
+#define MBED_TEXTLCD_H
+
+class TextLCD : public TextDisplay {
+	public:
+		TextLCD(PinName rs, PinName rw, PinName e,
+			    PinName d0, PinName d1, PinName d2, PinName d3,
+				uint16_t rows = 2, uint16_t columns = 16);
+		virtual void character(uint16_t column, uint16_t row, int c);
+		virtual uint16_t rows() { return _rows; }
+		virtual uint16_t columns() { return _columns; }
+		virtual void reset();
+		virtual void cls();
+
+		// locate, putc, printf come from parent class
+
+	protected:
+		void writeByte(uint16_t value);
+		void writeHalfByte(uint16_t value);
+		void writeCommand(uint16_t command);
+		void writeData(uint16_t data);
+		uint16_t readAddressAndBusy();
+		void waitUntilDone();
+
+		DigitalOut _rw, _rs, _e;
+		BusInOut _d;
+		uint16_t _rows, _columns;
+};
+
+#endif