/*
* LcdInit
* Description: This initializes the LCD. This must be called before the LCD can
* be used.
* Thus this function has to be called before calling any other
* LCD-interface functions.
* The LCD is set to the following specifications:
* 8-bit mode, 4-line display, 5x8 font
* cursor INCs, display doesn't shift
* cursor visible, cursor blinking
*
* Argument: None
* Return: None
*
* Input: None
* Output: LCD
*
* Operation:
* Really just follows standard initialization sequence. See sketch below
*
* POWER ON
* |
* | Wait time >40ms
* \|/
* FUNCTION SET (RS = 0, RW=0, DB = 0b0011NFXX) [BF cannot be checked b4 this]
* |
* | Wait time >37us
* \|/
* FUNCTION SET (RS = 0, RW=0, DB = 0b0011NFXX) [BF cannot be checked b4 this]
* |
* | Wait time >37us
* \|/
* DISPLAY ON/OFF control (RS = 0, RW=0, DB = 0b00001DCB)
* |
* | Wait time >37us
* \|/
* DISPLAY Clear (RS=0, RW=0, DB=0b00000001)
* |
* | Wait time >1.52ms
* \|/
* Entry Mode Set (RS=0, RW=0, DB=0b0000001{I/D}S)
* |
* | Wait time >37us
* \|/
* Initialization End
*
* Revision History:
* Dec. 16, 2012 Nnoduka Eruchalu Initial Revision
*/
void LcdInit(void)
{
LCD_DATA_TRIS = 0x00; /* setup LCD IO ports as outputs */
LCD_E_TRIS = 0;
LCD_RW_TRIS = 0;
LCD_RS_TRIS = 0;
LCD_DATA_LAT = 0; /* clear IO lines*/
CLEAR_RS(); CLEAR_RW(); CLEAR_E();
__delay_ms(40);
LCD_DATA_LAT = LCD_FUNC_SET; /* FUNCTION SET, done manually to prevent a */
LCD_STROBE(); /* BF check before next command */
__delay_us(40);
LcdCommand(LCD_FUNC_SET); /* FUNCTION SET, again done manually */
LCD_STROBE();
__delay_us(40);
LcdCommand(LCD_ON); /* DISPLAY ON/OFF control: Turn display on */
__delay_us(40);
LcdCommand(LCD_CLEAR); /* DISPLAY Clear */
__delay_ms(2);
LcdCommand(LCD_ENTRY_MD); /* ENTRY mode set */
GenSpecChars(); /* Now create some special characters */
}
/*
* LcdWaitBF
* Description: This procedure simply loops until the LCD is not busy.
* This clears the RS bit.
*
* Argument: None
* Return: None
*
* Input: LCD's Busy Flag
* Output: None
*
* Operation: Keep on looping and reading the LCD busy flag. Exit when it
* indicates the LCD is not busy.
*
* Revision History:
* Dec. 16, 2012 Nnoduka Eruchalu Initial Revision
*/
void LcdWaitBF(void)
{
unsigned char busy, status=0x00;
LCD_DATA_TRIS = 0xFF; /* when reading a port change it to an input */
CLEAR_RS(); /* prepare to read BF and Address Counter */
SET_RW(); /* and put the LCD in read mode */
do {
SET_E(); /* during reads the E has to be active */
__delay_us(0.5); /* wait tPW for data to become available */
status = LCD_DATA_PORT; /* read in value on data lines */
busy = status & 0x80; /* busy flag is highest status bit */
__delay_us(0.5);
CLEAR_E(); /* pull E low for at least tC-tPW */
__delay_us(1);
} while(busy);
/* put the LCD in write mode */
CLEAR_RW(); /* in write mode when R/W\ is cleared */
LCD_DATA_TRIS = 0x00; /* and the I/O pins are set as outputs */
}
/*
* LcdCommand
* Description: This procedure simply writes a command byte to the LCD.
* It does not return until the LCD's busy flag is cleared.
*
* Argument: c: command byte
* Return: None
*
* Input: None
* Output: LCD
*
* Operation: Send the byte, then wait for the BF to be cleared.
*
* Revision History:
* Dec. 16, 2012 Nnoduka Eruchalu Initial Revision
*/
void LcdCommand(unsigned char c)
{
LCD_DATA_LAT = c; /* put data on output port */
CLEAR_RS(); /* RS = 0: Command */
CLEAR_RW(); /* R/W = 0: Write */
LCD_STROBE();
LcdWaitBF(); /* dont exit until the LCD is no longer busy */
}
void LCDInit(uint8_t style)
{
/*****************************************************************
This function Initializes the lcd module
must be called before calling lcd related functions
Arguments:
style = LS_BLINK,LS_ULINE(can be "OR"ed for combination)
LS_BLINK : The cursor is blinking type
LS_ULINE : Cursor is "underline" type else "block" type
LS_NONE : No visible cursor
*****************************************************************/
//After power on Wait for LCD to Initialize
__delay_ms(30);
//Set IO Ports
LCD_DATA_TRIS&=(~(0x0F<<LCD_DATA_POS)); //Output
LCD_E_TRIS=0; //Output
LCD_RS_TRIS=0; //Output
LCD_RW_TRIS=0; //Output
LCD_DATA_PORT&=(~(0x0F<<LCD_DATA_POS));//Clear data port
CLEAR_E();
CLEAR_RW();
CLEAR_RS();
//Set 4-bit mode
__delay_us(0.5); //tAS
SET_E();
LCD_DATA_PORT|=((0b00000010)<<LCD_DATA_POS); //[B] To transfer 0b00100000 i was using LCD_DATA_PORT|=0b00100000
__delay_us(1);
CLEAR_E();
__delay_us(1);
//Wait for LCD to execute the Functionset Command
LCDBusyLoop(); //[B] Forgot this delay
//Now the LCD is in 4-bit mode
LCDCmd(0b00101000); //function set 4-bit,2 line 5x7 dot format
LCDCmd(0b00001100|style); //Display On
/* Custom Char */
LCDCmd(0b01000000);
uint8_t __i;
for(__i=0;__i<sizeof(__cgram);__i++)
LCDData(__cgram[__i]);
}
void LCDBusyLoop()
{
//This function waits till lcd is BUSY
uint8_t busy,status=0x00,temp;
//Change Port to input type because we are reading data
LCD_DATA_TRIS|=(0x0f<<LCD_DATA_POS);
//change LCD mode
SET_RW(); //Read mode
CLEAR_RS(); //Read status
//Let the RW/RS lines stabilize
__delay_us(0.5); //tAS
do
{
SET_E();
//Wait tDA for data to become available
__delay_us(0.5);
status=(LCD_DATA_PORT>>LCD_DATA_POS);
status=status<<4;
__delay_us(0.5);
//Pull E low
CLEAR_E();
__delay_us(1); //tEL
SET_E();
__delay_us(0.5);
temp=(LCD_DATA_PORT>>LCD_DATA_POS);
temp&=0x0F;
status=status|temp;
busy=status & 0b10000000;
__delay_us(0.5);
CLEAR_E();
__delay_us(1); //tEL
}while(busy);
CLEAR_RW(); //write mode
//Change Port to output
LCD_DATA_TRIS&=(~(0x0F<<LCD_DATA_POS));
}
void LCDByte(uint8_t c,uint8_t isdata)
{
//Sends a byte to the LCD in 4bit mode
//cmd=0 for data
//cmd=1 for command
//NOTE: THIS FUNCTION RETURS ONLY WHEN LCD HAS PROCESSED THE COMMAND
uint8_t hn,ln; //Nibbles
uint8_t temp;
hn=c>>4;
ln=(c & 0x0F);
if(isdata==0)
CLEAR_RS();
else
SET_RS();
_delay_us(0.500); //tAS
SET_E();
//Send high nibble
temp=(LCD_DATA_PORT & (~(0X0F<<LCD_DATA_POS)))|((hn<<LCD_DATA_POS));
LCD_DATA_PORT=temp;
_delay_us(1); //tEH
//Now data lines are stable pull E low for transmission
CLEAR_E();
_delay_us(1);
//Send the lower nibble
SET_E();
temp=(LCD_DATA_PORT & (~(0X0F<<LCD_DATA_POS)))|((ln<<LCD_DATA_POS));
LCD_DATA_PORT=temp;
_delay_us(1); //tEH
//SEND
CLEAR_E();
_delay_us(1); //tEL
LCDBusyLoop();
}
void LCDBusyLoop()
{
//This function waits till lcd is BUSY
uint8_t busy,status=0x00,temp;
//Change Port to input type because we are reading data
LCD_DATA_DDR&=0xF0;
//change LCD mode
SET_RW(); //Read mode
CLEAR_RS(); //Read status
//Let the RW/RS lines stabilize
_delay_us(HALF); //tAS
do
{
SET_E();
//Wait tDA for data to become available
_delay_us(HALF);
status=LCD_DATA_PIN;
status=status<<4;
_delay_us(HALF);
//Pull E low
CLEAR_E();
_delay_us(ONE); //tEL
SET_E();
_delay_us(HALF);
temp=LCD_DATA_PIN;
temp&=0x0F;
status=status|temp;
busy=status & 0b10000000;
_delay_us(HALF);
CLEAR_E();
_delay_us(ONE); //tEL
} while(busy);
CLEAR_RW(); //write mode
//Change Port to output
LCD_DATA_DDR|=0x0F;
}
void LCDInit(uint8_t style)
{
/*****************************************************************
This function Initializes the lcd module
must be called before calling lcd related functions
Arguments:
style = LS_BLINK,LS_ULINE(can be "OR"ed for combination)
LS_BLINK :The cursor is blinking type
LS_ULINE :Cursor is "underline" type else "block" type
*****************************************************************/
//After power on Wait for LCD to Initialize
_delay_ms(30);
//Set IO Ports
LCD_DATA_DDR|=(0x0F<<LCD_DATA_POS);
LCD_E_DDR|=(1<<LCD_E_POS);
LCD_RS_DDR|=(1<<LCD_RS_POS);
LCD_RW_DDR|=(1<<LCD_RW_POS);
LCD_DATA_PORT&=(~(0x0F<<LCD_DATA_POS));
CLEAR_E();
CLEAR_RW();
CLEAR_RS();
//Set 4-bit mode
_delay_us(0.3); //tAS
SET_E();
LCD_DATA_PORT|=((0b00000010)<<LCD_DATA_POS); //[B] To transfer 0b00100000 i was using LCD_DATA_PORT|=0b00100000
_delay_us(1);
CLEAR_E();
_delay_us(1);
//Wait for LCD to execute the Functionset Command
LCDBusyLoop(); //[B] Forgot this delay
//Now the LCD is in 4-bit mode
LCDCmd(0b00101000); //function set 4-bit,2 line 5x7 dot format
LCDCmd(0b00001100|style); //Display On
}
void LCDInit(uint8_t style)
{
__delay_ms(30);
//Set IO Ports
LCD_DATA_TRIS&=(~(0x0F<<LCD_DATA_POS)); //Output
LCD_E_TRIS=0; //Output
LCD_RS_TRIS=0; //Output
LCD_RW_TRIS=0; //Output
LCD_DATA_PORT&=(~(0x0F<<LCD_DATA_POS));//Clear data port
CLEAR_E();
CLEAR_RW();
CLEAR_RS();
//Set 4-bit mode
__delay_us(0.5); //tAS
SET_E();
LCD_DATA_PORT|=((0b00000010)<<LCD_DATA_POS); //[B] To transfer 0b00100000 i was using LCD_DATA_PORT|=0b00100000
__delay_us(1);
CLEAR_E();
__delay_us(1);
//Wait for LCD to execute the Functionset Command
LCDBusyLoop(); //[B] Forgot this delay
//Now the LCD is in 4-bit mode
LCDCmd(0b00101000); //function set 4-bit,2 line 5x7 dot format
LCDCmd(0b00001100|style); //Display On
/* Custom Char */
LCDCmd(0b01000000);
uint8_t __i;
for(__i=0;__i<sizeof(__cgram);__i++)
LCDData(__cgram[__i]);
}
