Migrating to Limor Fried's improved LiquidCrystal library.

2 files changed, 324 insertions, 68 deletions

diff --git a/libraries/LiquidCrystal/LiquidCrystal.cpp b/libraries/LiquidCrystal/LiquidCrystal.cpp
index b5f2cd4..4e46318 100755
--- a/libraries/LiquidCrystal/LiquidCrystal.cpp
+++ b/libraries/LiquidCrystal/LiquidCrystal.cpp
@@ -25,10 +25,39 @@
 // LiquidCrystal constructor is called).
 
 LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
-  uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
-  uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7) :
-  _four_bit_mode(0), _rs_pin(rs), _rw_pin(rw), _enable_pin(enable)
+			     uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
+			     uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
 {
+  init(0, rs, rw, enable, d0, d1, d2, d3, d4, d5, d6, d7);
+}
+
+LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t enable,
+			     uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
+			     uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
+{
+  init(0, rs, -1, enable, d0, d1, d2, d3, d4, d5, d6, d7);
+}
+
+LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
+			     uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3)
+{
+  init(1, rs, rw, enable, d0, d1, d2, d3, 0, 0, 0, 0);
+}
+
+LiquidCrystal::LiquidCrystal(uint8_t rs,  uint8_t enable,
+			     uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3)
+{
+  init(1, rs, -1, enable, d0, d1, d2, d3, 0, 0, 0, 0);
+}
+
+void LiquidCrystal::init(uint8_t fourbitmode, uint8_t rs, uint8_t rw, uint8_t enable,
+			 uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
+			 uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
+{
+  _rs_pin = rs;
+  _rw_pin = rw;
+  _enable_pin = enable;
+  
   _data_pins[0] = d0;
   _data_pins[1] = d1;
   _data_pins[2] = d2;
@@ -37,92 +66,244 @@ LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
   _data_pins[5] = d5;
   _data_pins[6] = d6;
   _data_pins[7] = d7; 
-  
+
   pinMode(_rs_pin, OUTPUT);
-  pinMode(_rw_pin, OUTPUT);
+  // we can save 1 pin by not using RW. Indicate by passing -1 instead of pin#
+  if (_rw_pin != -1) { 
+    pinMode(_rw_pin, OUTPUT);
+  }
   pinMode(_enable_pin, OUTPUT);
   
-  for (int i = 0; i < 8; i++)
-    pinMode(_data_pins[i], OUTPUT);
- 
-  command(0x38);  // function set: 8 bits, 1 line, 5x8 dots
-  command(0x0C);  // display control: turn display on, cursor off, no blinking
-  command(0x06);  // entry mode set: increment automatically, display shift, right shift
-  clear();
+  if (fourbitmode)
+    _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS;
+  else 
+    _displayfunction = LCD_8BITMODE | LCD_1LINE | LCD_5x8DOTS;
+  
+  begin(16, 1);  
 }
 
-LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
-  uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3) :
-  _four_bit_mode(1), _rs_pin(rs), _rw_pin(rw), _enable_pin(enable)
-{
-  _data_pins[0] = d0;
-  _data_pins[1] = d1;
-  _data_pins[2] = d2;
-  _data_pins[3] = d3; 
-  
-  pinMode(_rs_pin, OUTPUT);
-  pinMode(_rw_pin, OUTPUT);
-  pinMode(_enable_pin, OUTPUT);
+void LiquidCrystal::begin(uint8_t cols, uint8_t lines, uint8_t dotsize) {
+  if (lines > 1) {
+    _displayfunction |= LCD_2LINE;
+  }
+  _numlines = lines;
+  _currline = 0;
+
+  // for some 1 line displays you can select a 10 pixel high font
+  if ((dotsize != 0) && (lines == 1)) {
+    _displayfunction |= LCD_5x10DOTS;
+  }
+
+  // SEE PAGE 45/46 FOR INITIALIZATION SPECIFICATION!
+  // according to datasheet, we need at least 40ms after power rises above 2.7V
+  // before sending commands. Arduino can turn on way befer 4.5V so we'll wait 50
+  delayMicroseconds(50000); 
+  // Now we pull both RS and R/W low to begin commands
+  digitalWrite(_rs_pin, LOW);
+  digitalWrite(_enable_pin, LOW);
+  if (_rw_pin != -1) { 
+    digitalWrite(_rw_pin, LOW);
+  }
   
-  for (int i = 0; i < 4; i++)
-    pinMode(_data_pins[i], OUTPUT);
- 
-  command(0x28);  // function set: 4 bits, 1 line, 5x8 dots
-  command(0x0C);  // display control: turn display on, cursor off, no blinking
-  command(0x06);  // entry mode set: increment automatically, display shift, right shift
+  //put the LCD into 4 bit or 8 bit mode
+  if (! (_displayfunction & LCD_8BITMODE)) {
+    // this is according to the hitachi HD44780 datasheet
+    // figure 24, pg 46
+
+    // we start in 8bit mode, try to set 4 bit mode
+    write4bits(0x03);
+    delayMicroseconds(4500); // wait min 4.1ms
+
+    // second try
+    write4bits(0x03);
+    delayMicroseconds(4500); // wait min 4.1ms
+    
+    // third go!
+    write4bits(0x03); 
+    delayMicroseconds(150);
+
+    // finally, set to 8-bit interface
+    write4bits(0x02); 
+  } else {
+    // this is according to the hitachi HD44780 datasheet
+    // page 45 figure 23
+
+    // Send function set command sequence
+    command(LCD_FUNCTIONSET | _displayfunction);
+    delayMicroseconds(4500);  // wait more than 4.1ms
+
+    // second try
+    command(LCD_FUNCTIONSET | _displayfunction);
+    delayMicroseconds(150);
+
+    // third go
+    command(LCD_FUNCTIONSET | _displayfunction);
+  }
+
+  // finally, set # lines, font size, etc.
+  command(LCD_FUNCTIONSET | _displayfunction);  
+
+  // turn the display on with no cursor or blinking default
+  _displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF;  
+  display();
+
+  // clear it off
   clear();
+
+  // Initialize to default text direction (for romance languages)
+  _displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
+  // set the entry mode
+  command(LCD_ENTRYMODESET | _displaymode);
+
 }
 
+/********** high level commands, for the user! */
 void LiquidCrystal::clear()
 {
-  command(0x01);  // clear display, set cursor position to zero
-  delayMicroseconds(2000);
+  command(LCD_CLEARDISPLAY);  // clear display, set cursor position to zero
+  delayMicroseconds(2000);  // this command takes a long time!
 }
 
 void LiquidCrystal::home()
 {
-  command(0x02);  // set cursor position to zero
-  delayMicroseconds(2000);
+  command(LCD_RETURNHOME);  // set cursor position to zero
+  delayMicroseconds(2000);  // this command takes a long time!
 }
 
-void LiquidCrystal::setCursor(int col, int row)
+void LiquidCrystal::setCursor(uint8_t col, uint8_t row)
 {
   int row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };
-  command(0x80 | (col + row_offsets[row]));
+  if ( row > _numlines ) {
+    row = _numlines-1;    // we count rows starting w/0
+  }
+  
+  command(LCD_SETDDRAMADDR | (col + row_offsets[row]));
+}
+
+// Turn the display on/off (quickly)
+void LiquidCrystal::noDisplay() {
+  _displaycontrol &= ~LCD_DISPLAYON;
+  command(LCD_DISPLAYCONTROL | _displaycontrol);
+}
+void LiquidCrystal::display() {
+  _displaycontrol |= LCD_DISPLAYON;
+  command(LCD_DISPLAYCONTROL | _displaycontrol);
+}
+
+// Turns the underline cursor on/off
+void LiquidCrystal::noCursor() {
+  _displaycontrol &= ~LCD_CURSORON;
+  command(LCD_DISPLAYCONTROL | _displaycontrol);
+}
+void LiquidCrystal::cursor() {
+  _displaycontrol |= LCD_CURSORON;
+  command(LCD_DISPLAYCONTROL | _displaycontrol);
+}
+
+// Turn on and off the blinking cursor
+void LiquidCrystal::noBlink() {
+  _displaycontrol &= ~LCD_BLINKON;
+  command(LCD_DISPLAYCONTROL | _displaycontrol);
+}
+void LiquidCrystal::blink() {
+  _displaycontrol |= LCD_BLINKON;
+  command(LCD_DISPLAYCONTROL | _displaycontrol);
+}
+
+// These commands scroll the display without changing the RAM
+void LiquidCrystal::scrollDisplayLeft(void) {
+  command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVELEFT);
+}
+void LiquidCrystal::scrollDisplayRight(void) {
+  command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVERIGHT);
+}
+
+// This is for text that flows Left to Right
+void LiquidCrystal::shiftLeft(void) {
+  _displaymode |= LCD_ENTRYLEFT;
+  command(LCD_ENTRYMODESET | _displaymode);
+}
+
+// This is for text that flows Right to Left
+void LiquidCrystal::shiftRight(void) {
+  _displaymode &= ~LCD_ENTRYLEFT;
+  command(LCD_ENTRYMODESET | _displaymode);
+}
+
+// This will 'right justify' text from the cursor
+void LiquidCrystal::shiftIncrement(void) {
+  _displaymode |= LCD_ENTRYSHIFTINCREMENT;
+  command(LCD_ENTRYMODESET | _displaymode);
 }
 
-void LiquidCrystal::command(uint8_t value) {
+// This will 'left justify' text from the cursor
+void LiquidCrystal::shiftDecrement(void) {
+  _displaymode &= ~LCD_ENTRYSHIFTINCREMENT;
+  command(LCD_ENTRYMODESET | _displaymode);
+}
+
+// Allows us to fill the first 8 CGRAM locations
+// with custom characters
+void LiquidCrystal::createChar(uint8_t location, uint8_t charmap[]) {
+  location &= 0x7; // we only have 8 locations 0-7
+  command(LCD_SETCGRAMADDR | (location << 3));
+  for (int i=0; i<8; i++) {
+    write(charmap[i]);
+  }
+}
+
+/*********** mid level commands, for sending data/cmds */
+
+inline void LiquidCrystal::command(uint8_t value) {
   send(value, LOW);
 }
 
-void LiquidCrystal::write(uint8_t value) {
+inline void LiquidCrystal::write(uint8_t value) {
   send(value, HIGH);
 }
 
+/************ low level data pushing commands **********/
+
+// write either command or data, with automatic 4/8-bit selection
 void LiquidCrystal::send(uint8_t value, uint8_t mode) {
   digitalWrite(_rs_pin, mode);
-  digitalWrite(_rw_pin, LOW);
-
-  if (_four_bit_mode) {
-    for (int i = 0; i < 4; i++) {
-      digitalWrite(_data_pins[i], (value >> (i + 4)) & 0x01);
-    }
-    
-    digitalWrite(_enable_pin, HIGH);
-    digitalWrite(_enable_pin, LOW);
-    
-    for (int i = 0; i < 4; i++) {
-      digitalWrite(_data_pins[i], (value >> i) & 0x01);
-    }
 
-    digitalWrite(_enable_pin, HIGH);
-    digitalWrite(_enable_pin, LOW);
+  // if there is a RW pin indicated, set it low to Write
+  if (_rw_pin != -1) { 
+    digitalWrite(_rw_pin, LOW);
+  }
+  
+  if (_displayfunction & LCD_8BITMODE) {
+    write8bits(value); 
   } else {
-    for (int i = 0; i < 8; i++) {
-      digitalWrite(_data_pins[i], (value >> i) & 0x01);
-    }
+    write4bits(value>>4);
+    write4bits(value);
+  }
+}
+
+void LiquidCrystal::pulseEnable(void) {
+  digitalWrite(_enable_pin, LOW);
+  delayMicroseconds(1);    
+  digitalWrite(_enable_pin, HIGH);
+  delayMicroseconds(1);    // enable pulse must be >450ns
+  digitalWrite(_enable_pin, LOW);
+  delayMicroseconds(100);   // commands need > 37us to settle
+}
 
-    digitalWrite(_enable_pin, HIGH);
-    digitalWrite(_enable_pin, LOW);
+void LiquidCrystal::write4bits(uint8_t value) {
+  for (int i = 0; i < 4; i++) {
+    pinMode(_data_pins[i], OUTPUT);
+    digitalWrite(_data_pins[i], (value >> i) & 0x01);
   }
+
+  pulseEnable();
+}
+
+void LiquidCrystal::write8bits(uint8_t value) {
+  for (int i = 0; i < 8; i++) {
+    pinMode(_data_pins[i], OUTPUT);
+    digitalWrite(_data_pins[i], (value >> i) & 0x01);
+  }
+  
+  pulseEnable();
 }
diff --git a/libraries/LiquidCrystal/LiquidCrystal.h b/libraries/LiquidCrystal/LiquidCrystal.h
index a5edc5f..5a8d087 100755
--- a/libraries/LiquidCrystal/LiquidCrystal.h
+++ b/libraries/LiquidCrystal/LiquidCrystal.h
@@ -4,28 +4,103 @@
 #include <inttypes.h>
 #include "Print.h"
 
+// commands
+#define LCD_CLEARDISPLAY 0x01
+#define LCD_RETURNHOME 0x02
+#define LCD_ENTRYMODESET 0x04
+#define LCD_DISPLAYCONTROL 0x08
+#define LCD_CURSORSHIFT 0x10
+#define LCD_FUNCTIONSET 0x20
+#define LCD_SETCGRAMADDR 0x40
+#define LCD_SETDDRAMADDR 0x80
+
+// flags for display entry mode
+#define LCD_ENTRYRIGHT 0x00
+#define LCD_ENTRYLEFT 0x02
+#define LCD_ENTRYSHIFTINCREMENT 0x01
+#define LCD_ENTRYSHIFTDECREMENT 0x00
+
+// flags for display on/off control
+#define LCD_DISPLAYON 0x04
+#define LCD_DISPLAYOFF 0x00
+#define LCD_CURSORON 0x02
+#define LCD_CURSOROFF 0x00
+#define LCD_BLINKON 0x01
+#define LCD_BLINKOFF 0x00
+
+// flags for display/cursor shift
+#define LCD_DISPLAYMOVE 0x08
+#define LCD_CURSORMOVE 0x00
+#define LCD_MOVERIGHT 0x04
+#define LCD_MOVELEFT 0x00
+
+// flags for function set
+#define LCD_8BITMODE 0x10
+#define LCD_4BITMODE 0x00
+#define LCD_2LINE 0x08
+#define LCD_1LINE 0x00
+#define LCD_5x10DOTS 0x04
+#define LCD_5x8DOTS 0x00
+
 class LiquidCrystal : public Print {
 public:
-  LiquidCrystal(uint8_t, uint8_t, uint8_t, uint8_t, uint8_t, uint8_t, uint8_t);
-  LiquidCrystal(uint8_t, uint8_t, uint8_t, uint8_t, uint8_t, uint8_t, uint8_t,
-    uint8_t, uint8_t, uint8_t, uint8_t);
+  LiquidCrystal(uint8_t rs, uint8_t enable,
+		uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
+		uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7);
+  LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
+		uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
+		uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7);
+  LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
+		uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3);
+  LiquidCrystal(uint8_t rs, uint8_t enable,
+		uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3);
+
+  void init(uint8_t fourbitmode, uint8_t rs, uint8_t rw, uint8_t enable,
+	    uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
+	    uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7);
+    
+  void begin(uint8_t cols, uint8_t rows, uint8_t charsize = LCD_5x8DOTS);
+
   void clear();
   void home();
-  void setCursor(int, int); 
-  /*
-  void shiftDisplayLeft();
-  void shiftDisplayRight();
-  */
+
+  void noDisplay();
+  void display();
+  void noBlink();
+  void blink();
+  void noCursor();
+  void cursor();
+  void scrollDisplayLeft();
+  void scrollDisplayRight();
+  void printLeft();
+  void printRight();
+  void shiftLeft();
+  void shiftRight();
+  void shiftIncrement();
+  void shiftDecrement();
+
+  void createChar(uint8_t, uint8_t[]);
+  void setCursor(uint8_t, uint8_t); 
   virtual void write(uint8_t);
   void command(uint8_t);
 private:
   void send(uint8_t, uint8_t);
-  
-  uint8_t _four_bit_mode;
+  void write4bits(uint8_t);
+  void write8bits(uint8_t);
+  void pulseEnable();
+
   uint8_t _rs_pin; // LOW: command.  HIGH: character.
   uint8_t _rw_pin; // LOW: write to LCD.  HIGH: read from LCD.
   uint8_t _enable_pin; // activated by a HIGH pulse.
   uint8_t _data_pins[8];
+
+  uint8_t _displayfunction;
+  uint8_t _displaycontrol;
+  uint8_t _displaymode;
+
+  uint8_t _initialized;
+
+  uint8_t _numlines,_currline;
 };
 
 #endif