Wim Huiskamp / TextLCD

Updated for more display types. Fixed memoryaddress confusion in address() method. Added new getAddress() method. Added support for UDCs, Backlight control and other features such as control through I2C and SPI port expanders and controllers with native I2C and SPI interfaces. Refactored to fix issue with pins that are default declared as NC.

Dependents:   GPSDevice TestTextLCD SD to Flash Data Transfer DrumMachine ... more

Fork of TextLCD by Simon Ford

Example

Hello World! for the TextLCD

#include "mbed.h"
#include "TextLCD.h"
 
// Host PC Communication channels
Serial pc(USBTX, USBRX); // tx, rx
 
// I2C Communication
I2C i2c_lcd(p28,p27); // SDA, SCL
 
// SPI Communication
SPI spi_lcd(p5, NC, p7); // MOSI, MISO, SCLK

//TextLCD lcd(p15, p16, p17, p18, p19, p20);                // RS, E, D4-D7, LCDType=LCD16x2, BL=NC, E2=NC, LCDTCtrl=HD44780
//TextLCD_SPI lcd(&spi_lcd, p8, TextLCD::LCD40x4);   // SPI bus, 74595 expander, CS pin, LCD Type  
TextLCD_I2C lcd(&i2c_lcd, 0x42, TextLCD::LCD20x4);  // I2C bus, PCF8574 Slaveaddress, LCD Type
//TextLCD_I2C lcd(&i2c_lcd, 0x42, TextLCD::LCD16x2, TextLCD::WS0010); // I2C bus, PCF8574 Slaveaddress, LCD Type, Device Type
//TextLCD_SPI_N lcd(&spi_lcd, p8, p9);               // SPI bus, CS pin, RS pin, LCDType=LCD16x2, BL=NC, LCDTCtrl=ST7032_3V3   
//TextLCD_I2C_N lcd(&i2c_lcd, ST7032_SA, TextLCD::LCD16x2, NC, TextLCD::ST7032_3V3); // I2C bus, Slaveaddress, LCD Type, BL=NC, LCDTCtrl=ST7032_3V3  

int main() {
    pc.printf("LCD Test. Columns=%d, Rows=%d\n\r", lcd.columns(), lcd.rows());
    
    for (int row=0; row<lcd.rows(); row++) {
      int col=0;
      
      pc.printf("MemAddr(Col=%d, Row=%d)=0x%02X\n\r", col, row, lcd.getAddress(col, row));      
//      lcd.putc('-');
      lcd.putc('0' + row);      
      
      for (col=1; col<lcd.columns()-1; col++) {    
        lcd.putc('*');
      }
 
      pc.printf("MemAddr(Col=%d, Row=%d)=0x%02X\n\r", col, row, lcd.getAddress(col, row));      
      lcd.putc('+');
        
    }    
    
// Show cursor as blinking character
    lcd.setCursor(TextLCD::CurOff_BlkOn);
 
// Set and show user defined characters. A maximum of 8 UDCs are supported by the HD44780.
// They are defined by a 5x7 bitpattern. 
    lcd.setUDC(0, (char *) udc_0);  // Show |>
    lcd.putc(0);    
    lcd.setUDC(1, (char *) udc_1);  // Show <|
    lcd.putc(1);    

}

Handbook page

More info is here

Diff: TextLCD.h

Revision:
21:9eb628d9e164
Parent:
20:e0da005a777f
Child:
22:35742ec80c24
--- a/TextLCD.h	Mon May 13 19:29:13 2013 +0000
+++ b/TextLCD.h	Tue Apr 01 21:30:25 2014 +0000
@@ -7,6 +7,7 @@
  *               2013, v05: WH, Added support for 8x2B, added some UDCs  
  *               2013, v06: WH, Added support for devices that use internal DC/DC converters 
  *               2013, v07: WH, Added support for backlight and include portdefinitions for LCD2004 Module from DFROBOT
+ *               2014, v08: WH, Refactored in Base and Derived Classes to deal with mbed lib change regarding 'NC' defined DigitalOut pins
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -50,9 +51,9 @@
  * SPI spi_lcd(p5, NC, p7); // MOSI, MISO, SCLK
  *
  * TextLCD lcd(p15, p16, p17, p18, p19, p20);     // RS, E, D4-D7, LCDType=LCD16x2, BL=NC, E2=NC, LCDTCtrl=HD44780
- * //TextLCD lcd(&spi_lcd, p8, TextLCD::LCD40x4);   // SPI bus, CS pin, LCD Type  
- * //TextLCD lcd(&i2c_lcd, 0x42, TextLCD::LCD20x4); // I2C bus, PCF8574 Slaveaddress, LCD Type
- * //TextLCD lcd(&i2c_lcd, 0x42, TextLCD::LCD16x2, TextLCD::WS0010); // I2C bus, PCF8574 Slaveaddress, LCD Type, Device Type
+ * //TextLCD_SPI lcd(&spi_lcd, p8, TextLCD::LCD40x4);   // SPI bus, CS pin, LCD Type  
+ * //TextLCD_I2C lcd(&i2c_lcd, 0x42, TextLCD::LCD20x4); // I2C bus, PCF8574 Slaveaddress, LCD Type
+ * //TextLCD_I2C lcd(&i2c_lcd, 0x42, TextLCD::LCD16x2, TextLCD::WS0010); // I2C bus, PCF8574 Slaveaddress, LCD Type, Device Type
  * 
  * int main() {
  *   lcd.printf("Hello World!\n");
@@ -163,7 +164,7 @@
  * Currently supports 8x1, 8x2, 12x2, 12x4, 16x1, 16x2, 16x4, 20x2, 20x4, 24x2, 24x4, 40x2 and 40x4 panels
  *
  */
-class TextLCD : public Stream {
+class TextLCD_Base : public Stream {
 public:
 
     /** LCD panel format */
@@ -193,6 +194,8 @@
     };
 
 
+
+
     /** LCD Cursor control */
     enum LCDCursor {
         CurOff_BlkOff = 0x00,  /**<  Cursor Off, Blinking Char Off */    
@@ -214,37 +217,6 @@
         LightOn          /**<  Backlight On */            
     };
 
-    /** Create a TextLCD interface for using regular mbed pins
-     *
-     * @param rs    Instruction/data control line
-     * @param e     Enable line (clock)
-     * @param d4-d7 Data lines for using as a 4-bit interface
-     * @param type  Sets the panel size/addressing mode (default = LCD16x2)
-     * @param bl    Backlight control line (optional, default = NC)      
-     * @param e2    Enable2 line (clock for second controller, LCD40x4 only)  
-     * @param ctrl  LCD controller (default = HD44780)           
-     */
-    TextLCD(PinName rs, PinName e, PinName d4, PinName d5, PinName d6, PinName d7, LCDType type = LCD16x2, PinName bl = NC, PinName e2 = NC, LCDCtrl ctrl = HD44780);
-    
-    /** Create a TextLCD interface using an I2C PC8574 portexpander
-     *
-     * @param i2c             I2C Bus
-     * @param deviceAddress   I2C slave address (PCF8574)
-     * @param type            Sets the panel size/addressing mode (default = LCD16x2)
-     * @param ctrl            LCD controller (default = HD44780)                
-     */
-    TextLCD(I2C *i2c, char deviceAddress, LCDType type = LCD16x2, LCDCtrl ctrl = HD44780);
-
-
-    /** Create a TextLCD interface using an SPI 74595 portexpander
-     *
-     * @param spi             SPI Bus
-     * @param cs              chip select pin (active low)
-     * @param type            Sets the panel size/addressing mode (default = LCD16x2)
-     * @param ctrl            LCD controller (default = HD44780)                     
-     */
-    TextLCD(SPI *spi, PinName cs, LCDType type = LCD16x2, LCDCtrl ctrl = HD44780);
-
 
 #if DOXYGEN_ONLY
     /** Write a character to the LCD
@@ -312,13 +284,13 @@
      *
      * @param displayMode The Display mode (DispOff, DispOn)
      */
-    void setMode(TextLCD::LCDMode displayMode);     
+    void setMode(LCDMode displayMode);     
 
     /** Set the Backlight mode
      *
-     * @param backlightMode The Backlight mode (LightOff, LightOn)
+     *  @param backlightMode The Backlight mode (LightOff, LightOn)
      */
-    void setBacklight(TextLCD::LCDBacklight backlightMode); 
+    void setBacklight(LCDBacklight backlightMode); 
 
 
     /** Set User Defined Characters
@@ -330,70 +302,55 @@
 
 
 protected:
-   /* LCD Bus control */
-    enum _LCDBus {
-        _PinBus,  /*<  Regular mbed pins */    
-        _I2CBus,  /*<  I2C PCF8574 Portexpander */    
-        _SPIBus   /*<  SPI 74595 Shiftregister */    
-    };
 
-   /* LCD controller select, mainly used for LCD40x4 */
+   /** LCD controller select, mainly used for LCD40x4
+     */
     enum _LCDCtrl_Idx {
         _LCDCtrl_0,  /*<  Primary */    
         _LCDCtrl_1,  /*<  Secondary */            
     };
+
+    /** Create a TextLCD_Base interface
+      * @brief Base class, can not be instantiated
+      *
+      * @param type  Sets the panel size/addressing mode (default = LCD16x2)
+      * @param ctrl  LCD controller (default = HD44780)           
+      */
+    TextLCD_Base(LCDType type = LCD16x2, LCDCtrl ctrl = HD44780);
+
     
     // Stream implementation functions
     virtual int _putc(int value);
     virtual int _getc();
 
-//Low level methods for LCD controller
+/** Low level methods for LCD controller
+  */
     void _init();    
     void _initCtrl();    
     int  _address(int column, int row);
-    void _setCursor(TextLCD::LCDCursor show);
+    void _setCursor(LCDCursor show);
     void _setUDC(unsigned char c, char *udc_data);   
-    void _setCursorAndDisplayMode(TextLCD::LCDMode displayMode, TextLCD::LCDCursor cursorType);       
+    void _setCursorAndDisplayMode(LCDMode displayMode, LCDCursor cursorType);       
     
-//Low level write operations to LCD controller
+/** Low level write operations to LCD controller
+  */
     void _writeNibble(int value);
     void _writeByte(int value);
     void _writeCommand(int command);
     void _writeData(int data);
 
-//Low level writes to LCD Bus (serial or parallel)
-    void _setEnable(bool value);
-    void _setRS(bool value);  
-    void _setBL(bool value);
-    void _setData(int value);
-    void _setCS(bool value);
-    
-//Low level writes to LCD serial bus only
-    void _writeBus();      
+/** Pure Virtual Low level writes to LCD Bus (serial or parallel)
+  */
+    virtual void _setEnable(bool value) = 0;
+    virtual void _setRS(bool value) = 0;  
+    virtual void _setBL(bool value) = 0;
+    virtual void _setData(int value) = 0;
 
-  
-// Regular mbed pins bus
-    DigitalOut _rs, _e, _bl, _e2;
-    BusOut _d;
-    
-// I2C bus    
-    I2C *_i2c;
-    unsigned char _slaveAddress;
-    
-// SPI bus        
-    SPI *_spi;
-    DigitalOut _cs;    
-    
-//Bus Interface type    
-    _LCDBus _busType;
-
-// Internal bus mirror value for serial bus only
-    char _lcd_bus;   
     
 //Display type
     LCDType _type;
 
-//Display type
+//Display mode
     LCDMode _currentMode;
 
 //Controller type 
@@ -408,4 +365,104 @@
     LCDCursor _currentCursor;    
 };
 
+
+/** Create a TextLCD interface for using regular mbed pins
+  *
+  */
+class TextLCD : public TextLCD_Base {
+public:    
+    /** Create a TextLCD interface for using regular mbed pins
+     *
+     * @param rs    Instruction/data control line
+     * @param e     Enable line (clock)
+     * @param d4-d7 Data lines for using as a 4-bit interface
+     * @param type  Sets the panel size/addressing mode (default = LCD16x2)
+     * @param bl    Backlight control line (optional, default = NC)      
+     * @param e2    Enable2 line (clock for second controller, LCD40x4 only)  
+     * @param ctrl  LCD controller (default = HD44780)           
+     */
+    TextLCD(PinName rs, PinName e, PinName d4, PinName d5, PinName d6, PinName d7, LCDType type = LCD16x2, PinName bl = NC, PinName e2 = NC, LCDCtrl ctrl = HD44780);
+
+private:    
+//Low level writes to LCD Bus (serial or parallel)
+    virtual void _setEnable(bool value);
+    virtual void _setRS(bool value);  
+    virtual void _setBL(bool value);
+    virtual void _setData(int value);
+
+// Regular mbed pins bus
+    DigitalOut _rs, _e, _bl, _e2;
+    BusOut _d;   
+};
+
+
+
+/** Create a TextLCD interface using an I2C PC8574 portexpander
+  *
+  */
+class TextLCD_I2C : public TextLCD_Base {    
+public:
+    /** Create a TextLCD interface using an I2C PC8574 portexpander
+     *
+     * @param i2c             I2C Bus
+     * @param deviceAddress   I2C slave address (PCF8574)
+     * @param type            Sets the panel size/addressing mode (default = LCD16x2)
+     * @param ctrl            LCD controller (default = HD44780)                
+     */
+    TextLCD_I2C(I2C *i2c, char deviceAddress, LCDType type = LCD16x2, LCDCtrl ctrl = HD44780);
+
+private:
+//Low level writes to LCD Bus (serial or parallel)
+    virtual void _setEnable(bool value);
+    virtual void _setRS(bool value);  
+    virtual void _setBL(bool value);
+    virtual void _setData(int value);   
+  
+//I2C bus
+    I2C *_i2c;
+    char _slaveAddress;
+    
+// Internal bus mirror value for serial bus only
+    char _lcd_bus;   
+    
+};
+
+
+
+/** Create a TextLCD interface using an SPI 74595 portexpander
+  *
+  */
+class TextLCD_SPI : public TextLCD_Base {    
+public:
+    /** Create a TextLCD interface using an SPI 74595 portexpander
+     *
+     * @param spi             SPI Bus
+     * @param cs              chip select pin (active low)
+     * @param type            Sets the panel size/addressing mode (default = LCD16x2)
+     * @param ctrl            LCD controller (default = HD44780)                     
+     */
+    TextLCD_SPI(SPI *spi, PinName cs, LCDType type = LCD16x2, LCDCtrl ctrl = HD44780);
+
+
+private:
+//Low level writes to LCD Bus (serial or parallel)
+    virtual void _setEnable(bool value);
+    virtual void _setRS(bool value);  
+    virtual void _setBL(bool value);
+    virtual void _setData(int value);
+    virtual void _setCS(bool value);
+    
+//Low level writes to LCD serial bus only
+    void _writeBus();      
+   
+// SPI bus        
+    SPI *_spi;
+    DigitalOut _cs;    
+    
+// Internal bus mirror value for serial bus only
+    char _lcd_bus;   
+
+};
+
+
 #endif