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:
24:fb3399713710
Parent:
23:d47f226efb24
Child:
25:6162b31128c9
--- a/TextLCD.cpp	Wed Apr 02 18:16:37 2014 +0000
+++ b/TextLCD.cpp	Sat May 10 13:50:25 2014 +0000
@@ -111,7 +111,18 @@
           wait_ms(50);
         
           break;
-
+      case ST7032:
+          _writeByte( 0x1c );   //Internal OSC frequency adjustment 183HZ    bias will be 1/4 
+          wait_us(30);
+          _writeByte( 0x73 );    //Contrast control  low byte
+          wait_us(30);  
+          _writeByte( 0x57 );    //booster circuit is turn on.    /ICON display off. /Contrast control   high byte
+          wait_us(30);
+          _writeByte( 0x6c );  //Follower control
+          wait_us(50);   
+          _writeByte( 0x0c );    //DISPLAY ON
+          wait_us(30);
+          break;
       case WS0010:         
           // WS0010 OLED controller: Initialise DC/DC Voltage converter for LEDs
           // Note: supports 1 or 2 lines (and 16x100 graphics)
@@ -1107,6 +1118,77 @@
 //---------- End TextLCD_SPI ------------
 
 
+//--------- Start TextLCD_NativeSPI -----------
+
+ /** 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_NativeSPI::TextLCD_NativeSPI(SPI *spi, PinName cs, PinName rs, LCDType type, PinName bl, LCDCtrl ctrl) :
+                         TextLCD_Base(type, ctrl), 
+                         _spi(spi),        
+                         _cs(cs),
+                         _rs(rs) {      
+        
+  // Setup the spi for 8 bit data, low steady state clock,
+  // rising edge capture, with a 500KHz or 1MHz clock rate  
+  _spi->format(8,0);
+  _spi->frequency(1000000);    
+  
+  // The hardware Backlight pin is optional. Test and make sure whether it exists or not to prevent illegal access.
+  if (bl != NC) {
+    _bl = new DigitalOut(bl);   //Construct new pin 
+    _bl->write(0);              //Deactivate    
+  }
+  else {
+    // No Hardware Backlight pin       
+    _bl = NULL;                 //Construct dummy pin     
+  }  
+  
+  _writeByte( 0x39 );  //FUNCTION SET 8 bit,N=1 2-line display mode,5*7dot IS=1
+  wait_us(30);
+  _init();
+}
+
+TextLCD_NativeSPI::~TextLCD_NativeSPI() {
+   if (_bl != NULL) {delete _bl;}  // BL pin
+}
+
+// Not used in this mode
+void TextLCD_NativeSPI::_setEnable(bool value) {
+}    
+
+// Set RS pin
+// Used for mbed pins, I2C bus expander or SPI shiftregister
+void TextLCD_NativeSPI::_setRS(bool value) {
+    _rs = value;
+}    
+
+// Set BL pin
+void TextLCD_NativeSPI::_setBL(bool value) {
+    if (_bl)
+        _bl->write(value);   
+}    
+
+// Write a byte using SPI
+void TextLCD_NativeSPI::_writeByte(int value) {
+    _cs = 0;
+    wait_us(1);
+    _spi->write(value);
+    wait_us(1);
+    _cs = 1;
+}
+    
+
+// Not used in this mode
+void TextLCD_NativeSPI::_setData(int value) {
+}    
+
+
+//---------- End TextLCD_NativeSPI ------------