lcd_lpc23xx.c

Show Interworking of ARM/Thumb code on LPC23xx

/* 
 ********************************************************************
 * 
 * File:    	LCD_LPC23xx.h
 *
 * System:   	ARM7TDMI-S 32 Bit
 * 
 * Compiler:  	GCC 4.0.0.0
 *
 * Date:      	2006-08-25
 *
 * Author:    	Wenz
 *
 * Rights:    	Hitex Development Tools GmbH
 *            	Greschbachstr. 12
 *            	D-76229 Karlsruhe
 * 
 ********************************************************************
 * Description
 *	
 *	driver for LCD module (A162) 2x16 on board MCB2300 
 *
 ********************************************************************
 *
 * History:
 *
 *      Initial revision
 * 
 * 
 ********************************************************************
 */


#include "lpc23xx.h"                   /* LPC23xx definitions               */
#include "LCD_LPC23xx.h"


/* LCD  definitions */
#define LCD_E     0x40000000            /* Enable control pin                */
#define LCD_RW    0x20000000            /* Read/Write control pin            */
#define LCD_RS    0x10000000            /* Data/Instruction control          */
#define LCD_CTRL  0x70000000            /* Control lines mask                */
#define LCD_DATA  0x0F000000            /* Data lines mask                   */


/* Local variables */
static uint32_t 	lcd_ptr;


/* 8 user defined characters to be loaded into CGRAM (used for bargraph) */
static const uint8_t UserFont[8][8] = 
{
  { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 },
  { 0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10 },
  { 0x18,0x18,0x18,0x18,0x18,0x18,0x18,0x18 },
  { 0x1C,0x1C,0x1C,0x1C,0x1C,0x1C,0x1C,0x1C },
  { 0x1E,0x1E,0x1E,0x1E,0x1E,0x1E,0x1E,0x1E },
  { 0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F },
  { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 },
  { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }
};

/* Local Function Prototypes */
static void 		prvDelay (uint32_t cnt);
static void 		prvLCDWrite (uint32_t c);
static void 		prvLCDWrite4Bit (uint32_t c);
static uint32_t 	prvLCDReadStat(void);
static void 		prvLCDWriteCommand (uint32_t c);
static void 		prvLCDWriteData (uint32_t d);
static void 		prvLCDWaitForBusy (void);



/****************************************************************************
* Name:			prvDelay
*                  	
* Description:	a cycle delay function
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/

static void prvDelay(uint32_t aCount) 
{
   while (aCount--);
}


/****************************************************************************
* Name:			prvLCDWrite
*                  	
* Description:	Write a 4-bit command to LCD controller.
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/

static void prvLCDWrite4Bit(uint32_t c)
{

   IODIR1 |= LCD_DATA | LCD_CTRL;
   IOCLR1  = LCD_RW   | LCD_DATA;
   IOSET1  = (c & 0xF) << 24;
   IOSET1  = LCD_E;
   prvDelay (10);
   IOCLR1  = LCD_E;
   prvDelay (10);
}
/****************************************************************************
* Name:			prvLCDWrite
*                  	
* Description:	Write data/command to LCD controller.
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/

static void prvLCDWrite (uint32_t c)
{
   prvLCDWrite4Bit(c >> 4);
   prvLCDWrite4Bit(c);
}


/****************************************************************************
* Name:			prvLCDReadStatus
*                  	
* Description:	 Read status of LCD controller
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/

static uint32_t prvLCDReadStat (void)
{
   uint32_t stat;

   IODIR1 &= ~LCD_DATA;
   IOCLR1  = LCD_RS;
   IOSET1  = LCD_RW;
   prvDelay (10);
   IOSET1  = LCD_E;
   prvDelay (10);
   stat    = (IOPIN1 >> 20) & 0xF0;
   IOCLR1  = LCD_E;
   prvDelay (10);
   IOSET1  = LCD_E;
   prvDelay (10);
   stat   |= (IOPIN1 >> 24) & 0xF;
   IOCLR1  = LCD_E;
   return (stat);
}
/****************************************************************************
* Name:		prvLCDWaitForBusy
*                  	
* Description:	Wait until LCD controller is busy.
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
static void prvLCDWaitForBusy (void) 
{
   uint32_t stat;

   do
   {
      stat = prvLCDReadStat();
   }
   while (stat & 0x80);               /* Wait for busy flag                */
}
/****************************************************************************
* Name:		prvLCDWriteCommand
*                  	
* Description:	Write command to LCD controller.
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
static void prvLCDWriteCommand (uint32_t c) 
{
   prvLCDWaitForBusy ();
   IOCLR1 = LCD_RS;
   prvLCDWrite(c);
}
/****************************************************************************
* Name:		prvLCDWriteData
*                  	
* Description:	Write data to LCD controller.
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
static void prvLCDWriteData (uint32_t data)
{
   prvLCDWaitForBusy ();
   IOSET1 = LCD_RS;
   prvLCDWrite(data);
}
/****************************************************************************
* Name:		vLCDInit
*                  	
* Description:	Initialize the LCD controller to 4-bit mode.
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDInit (void)
{
   IODIR1 |= LCD_CTRL | LCD_DATA;
   IOCLR1  = LCD_RW   | LCD_RS   | LCD_DATA;

   prvLCDWrite4Bit(0x3);                /* Select 4-bit interface            */
   prvDelay (100000);
   prvLCDWrite4Bit (0x3);
   prvDelay (10000);
   prvLCDWrite4Bit (0x3);
   prvLCDWrite4Bit (0x2);

   prvLCDWriteCommand (0x28);                   /* 2 lines, 5x8 character matrix     */
   prvLCDWriteCommand (0x0e);                   /* Display ctrl:Disp/Curs/Blnk=ON    */
   prvLCDWriteCommand (0x06);                   /* Entry mode: Move right, no shift  */

   vLCDLoad((uint8_t*)&UserFont, sizeof (UserFont));
   vLCDCls();
}
/****************************************************************************
* Name:		vLCDLoad
*                  	
* Description:	Load user-specific characters into CGRAM
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDLoad (uint8_t *fp, uint32_t cnt)
{
   uint32_t i;

   prvLCDWriteCommand (0x40);                   /* Set CGRAM address counter to 0    */
   for (i = 0; i < cnt; i++, fp++)  {
      prvLCDWriteData (*fp);
   }
}
/****************************************************************************
* Name:		vLCDGoto
*                  	
* Description:	Set cursor position on LCD display. Left corner: 1,1, right: 16,2 
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDGoto (uint32_t x, uint32_t y)
{
   uint32_t c;

   c = --x;
   if (--y) {
      c |= 0x40;
   }
   prvLCDWriteCommand (c | 0x80);
   lcd_ptr = y*16 + x;
}
/****************************************************************************
* Name:		vLCDCls
*                  	
* Description:	Clear LCD display, move cursor to home position.  
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDCls (void)
{
   prvLCDWriteCommand (0x01);
   vLCDGoto(1,1);
}
/****************************************************************************
* Name:		vLCDCursorOff
*                  	
* Description:	Switch off LCD cursor. 
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDCursorOff(void)
{
   prvLCDWriteCommand (0x0c);
}
/****************************************************************************
* Name:		vLCDsSwitchOn
*                  	
* Description:	Switch on LCD and enable cursor. 
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDsSwitchOn(void)
{
   prvLCDWriteCommand (0x0e);
}
/****************************************************************************
* Name:		vLCDPutc
*                  	
* Description:	Print a character to LCD at current cursor position. 
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDPutc (int8_t c)
{ 
   if (lcd_ptr == 16) {
      prvLCDWriteCommand (0xc0);
   }
   prvLCDWriteData (c);
   lcd_ptr++;
}
/****************************************************************************
* Name:		vLCDPuts
*                  	
* Description:	Print a string to LCD at current cursor position. 
*						
* Parameters:	none
*					
* Return value:	none
****************************************************************************
*/
void vLCDPuts (int8_t *sp) 
{
   while (*sp)
   {
      vLCDPutc (*sp++);
   }
}
/****************************************************************************
* Name:		vLCDPuts
*                  	
* Description:	Print a bargraph to LCD display.
*                                  
* Parameters:	- val:  value 0..100 %
*               - size: size of bargraph 1..16
*					
* Return value:	none
****************************************************************************
*/
void vLCDBargraph (uint32_t val, uint32_t size)
{
   uint32_t i;

   val = val * size / 20;               /* Display matrix 5 x 8 pixels       */
   for (i = 0; i < size; i++)
   {
      if (val > 5)
      {
         vLCDPutc (5);
         val -= 5;
      }
      else
      {
         vLCDPutc (val);
         break;
      }
   }
}

/*----------------------------------------------------------------------------
 * end of file
 *---------------------------------------------------------------------------*/