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.cpp

Revision:
35:311be6444a39
Parent:
34:e5a0dcb43ecc
Child:
36:9f5f86dfd44a
--- a/TextLCD.cpp	Sat Sep 27 12:38:27 2014 +0000
+++ b/TextLCD.cpp	Fri Oct 10 15:47:56 2014 +0000
@@ -15,6 +15,7 @@
  *               2014, v13: WH, Added support for controllers US2066/SSD1311 (OLED), added setUDCBlink() method for supported devices (eg SSD1803), fixed issue in setPower() 
  *               2014, v14: WH, Added support for PT6314 (VFD), added setOrient() method for supported devices (eg SSD1803, US2066), added Double Height lines for supported devices, 
  *                              added 16 UDCs for supported devices (eg PCF2103), moved UDC defines to TextLCD_UDC file, added TextLCD_Config.h for feature and footprint settings.
+ *               2014, v15: WH, Added AC780 support, added I2C expander modules, fixed setBacklight() for inverted logic modules. Fixed bug in LCD_SPI_N define 
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -1574,12 +1575,23 @@
   */
 void TextLCD_Base::setBacklight(LCDBacklight backlightMode) {
 
+#if (BACKLIGHT_INV==0)      
+    // Positive Backlight control pin logic
     if (backlightMode == LightOn) {
-      this->_setBL(true);
+      this->_setBL(true);     
     }
     else {
       this->_setBL(false);    
     }
+#else
+    // Inverted Backlight control pin logic
+    if (backlightMode == LightOn) {
+      this->_setBL(false);    
+    }
+    else {
+      this->_setBL(true);           
+    }
+#endif    
 } 
 
 /** Set User Defined Characters
@@ -1614,28 +1626,6 @@
   }   
 }
 
-
-#if(0)
-/** Low level method to store user defined characters for current controller
-  *
-  * @param unsigned char c   The Index of the UDC (0..7) for HD44780 clones 
-  * @param char *udc_data    The bitpatterns for the UDC (8 bytes of 5 significant bits)     
-  */     
-void TextLCD_Base::_setUDC(unsigned char c, char *udc_data) {
-  
-  // Select CG RAM for current LCD controller
-  _writeCommand(0x40 + ((c & 0x07) << 3)); //Set CG-RAM address,
-                                           //8 sequential locations needed per UDC
-  // Store UDC pattern 
-  for (int i=0; i<8; i++) {
-    _writeData(*udc_data++);
-  }
-   
-  //Select DD RAM again for current LCD controller
-  int addr = getAddress(_column, _row);
-  _writeCommand(0x80 | addr);  
-}
-#else
 /** Low level method to store user defined characters for current controller
   *
   * @param unsigned char c   The Index of the UDC (0..7) for HD44780 clones and (0..15) for some more advanced controllers 
@@ -1673,7 +1663,6 @@
   int addr = getAddress(_column, _row);
   _writeCommand(0x80 | addr);  
 }
-#endif
 
 /** Set UDC Blink
   * setUDCBlink method is supported by some compatible devices (eg SSD1803) 
@@ -2322,10 +2311,6 @@
 // Used for mbed pins, I2C bus expander or SPI shiftregister
 void TextLCD_I2C::_setBL(bool value) {
 
-#if (DFROBOT==1)  
-  value = !value; // The DFRobot module uses PNP transistor to drive the Backlight. Reverse logic level.
-#endif
-  
   if (value) {
     _lcd_bus |= D_LCD_BL;    // Set BL bit 
   }