Upgrade LiquidCrystal driver to recent version and add Prusa custom mods.

Firmware/LiquidCrystal.cpp

@@ -21,7 +21,7 @@
 //    S = 0; No shift 
 //
 // Note, however, that resetting the Arduino doesn't reset the LCD, so we
-// can't assume that it's in that state when a sketch starts (and the
+// can't assume that its in that state when a sketch starts (and the
 // LiquidCrystal constructor is called).
 
 LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
@@ -67,13 +67,6 @@ void LiquidCrystal::init(uint8_t fourbitmode, uint8_t rs, uint8_t rw, uint8_t en
   _data_pins[6] = d6;
   _data_pins[7] = d7; 
 
-  pinMode(_rs_pin, OUTPUT);
-  // we can save 1 pin by not using RW. Indicate by passing 255 instead of pin#
-  if (_rw_pin != 255) { 
-    pinMode(_rw_pin, OUTPUT);
-  }
-  pinMode(_enable_pin, OUTPUT);
-  
   if (fourbitmode)
     _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS;
   else 
@@ -82,21 +75,36 @@ void LiquidCrystal::init(uint8_t fourbitmode, uint8_t rs, uint8_t rw, uint8_t en
   begin(16, 1);  
 }
 
-void LiquidCrystal::begin(uint8_t cols, uint8_t lines, uint8_t dotsize) {
+void LiquidCrystal::begin(uint8_t cols, uint8_t lines, uint8_t dotsize, bool noclear) {
+
   if (lines > 1) {
     _displayfunction |= LCD_2LINE;
   }
   _numlines = lines;
-  _currline = 0;
+
+  setRowOffsets(0x00, 0x40, 0x00 + cols, 0x40 + cols);  
 
   // for some 1 line displays you can select a 10 pixel high font
-  if ((dotsize != 0) && (lines == 1)) {
+  if ((dotsize != LCD_5x8DOTS) && (lines == 1)) {
     _displayfunction |= LCD_5x10DOTS;
   }
 
+  pinMode(_rs_pin, OUTPUT);
+  // we can save 1 pin by not using RW. Indicate by passing 255 instead of pin#
+  if (_rw_pin != 255) { 
+    pinMode(_rw_pin, OUTPUT);
+  }
+  pinMode(_enable_pin, OUTPUT);
+  
+  // Do these once, instead of every time a character is drawn for speed reasons.
+  for (int i=0; i<((_displayfunction & LCD_8BITMODE) ? 8 : 4); ++i)
+  {
+    pinMode(_data_pins[i], OUTPUT);
+   } 
+
   // 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
+  // before sending commands. Arduino can turn on way before 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);
@@ -142,137 +150,66 @@ void LiquidCrystal::begin(uint8_t cols, uint8_t lines, uint8_t dotsize) {
 
   // finally, set # lines, font size, etc.
   command(LCD_FUNCTIONSET | _displayfunction);  
-  delayMicroseconds(60);
+
   // turn the display on with no cursor or blinking default
   _displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF;  
   display();
-  delayMicroseconds(60);
-  // clear it off
-  clear();
-  delayMicroseconds(3000);
-  // Initialize to default text direction (for romance languages)
-  _displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
-  // set the entry mode
-  command(LCD_ENTRYMODESET | _displaymode);
-  delayMicroseconds(60);
 
-}
+  if (noclear) {
-
+    home();
-
-
-void LiquidCrystal::begin_noclear(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 != 255) { 
-    digitalWrite(_rw_pin, LOW);
-  }
-  
-  //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 4-bit interface
-    write4bits(0x02); 
   } else {
-    // this is according to the hitachi HD44780 datasheet
+    // clear it off
-    // page 45 figure 23
+    clear();
-
-    // 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);  
-  delayMicroseconds(60);
-
-  // turn the display on with no cursor or blinking default
-  _displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF;  
-  display();
-  delayMicroseconds(60);
-  // clear it off
-  //clear();
-
-  home();
-  delayMicroseconds(1600);
   // Initialize to default text direction (for romance languages)
   _displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
   // set the entry mode
   command(LCD_ENTRYMODESET | _displaymode);
-  delayMicroseconds(60);
-
-  setCursor(8,0);
-  print("    ");
-  setCursor(8,1);
-  print("    ");
-  setCursor(6,2);
-  print("      ");
 
+  if (noclear) {
+    setCursor(8,0);
+    print("    ");
+    setCursor(8,1);
+    print("    ");
+    setCursor(6,2);
+    print("      ");
+  }
 
 }
 
-
+void LiquidCrystal::setRowOffsets(int row0, int row1, int row2, int row3)
-
+{
+  _row_offsets[0] = row0;
+  _row_offsets[1] = row1;
+  _row_offsets[2] = row2;
+  _row_offsets[3] = row3;
+}
 
 /********** high level commands, for the user! */
 void LiquidCrystal::clear()
 {
   command(LCD_CLEARDISPLAY);  // clear display, set cursor position to zero
-  delayMicroseconds(1600);  // this command takes a long time
+  delayMicroseconds(2000);  // this command takes a long time!
-  
 }
 
 void LiquidCrystal::home()
 {
   command(LCD_RETURNHOME);  // set cursor position to zero
-  delayMicroseconds(1600);  // this command takes a long time!
+  delayMicroseconds(2000);  // this command takes a long time!
-  
 }
 
 void LiquidCrystal::setCursor(uint8_t col, uint8_t row)
 {
-  int row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };
+  const size_t max_lines = sizeof(_row_offsets) / sizeof(*_row_offsets);
+  if ( row >= max_lines ) {
+    row = max_lines - 1;    // we count rows starting w/0
+  }
   if ( row >= _numlines ) {
-    row = _numlines-1;    // we count rows starting w/0
+    row = _numlines - 1;    // we count rows starting w/0
   }
   
-  command(LCD_SETDDRAMADDR | (col + row_offsets[row]));
+  command(LCD_SETDDRAMADDR | (col + _row_offsets[row]));
 }
 
 // Turn the display on/off (quickly)
@@ -388,7 +325,6 @@ void LiquidCrystal::pulseEnable(void) {
 
 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);
   }
 
@@ -397,7 +333,6 @@ void LiquidCrystal::write4bits(uint8_t value) {
 
 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);
   }
   

Firmware/LiquidCrystal.h

@@ -59,9 +59,7 @@ public:
 	    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 begin(uint8_t cols, uint8_t rows, uint8_t charsize = LCD_5x8DOTS, bool noclear = false);
-
-  void begin_noclear(uint8_t cols, uint8_t rows, uint8_t charsize = LCD_5x8DOTS);
 
   void clear();
   void home();
@@ -79,6 +77,7 @@ public:
   void autoscroll();
   void noAutoscroll();
 
+  void setRowOffsets(int row1, int row2, int row3, int row4);
   void createChar(uint8_t, uint8_t[]);
   void setCursor(uint8_t, uint8_t); 
   virtual size_t write(uint8_t);
@@ -102,7 +101,8 @@ private:
 
   uint8_t _initialized;
 
-  uint8_t _numlines,_currline;
+  uint8_t _numlines;
+  uint8_t _row_offsets[4];
 };
 
 #endif

Firmware/ultralcd_implementation_hitachi_HD44780.h

@@ -591,7 +591,7 @@ static void lcd_implementation_init_noclear(
       lcd.backlight();
     
 #else
-    lcd.begin_noclear(LCD_WIDTH, LCD_HEIGHT);
+    lcd.begin(LCD_WIDTH, LCD_HEIGHT, LCD_5x8DOTS, true);
 #endif
 
     lcd_set_custom_characters(