UART Transmission in LPC2378

below i commented the pupose of those two lines...

   PCONP |= 0x00000010;                    /* To Enable the power/clock control bit for UART1   */
    PCLKSEL0 |= 0x00000300;                     /* To Enable the Peripheral clock selection for UART1*/

I am using TxD1 and RxD1 in P0.i commented below..

PINSEL0 |= 0x40000000;          /* Enable TxD1 in P0.15                                */
PINSEL1 |= 0x00000001;                  /* Enable RxD1 in P0.16                             */

Now i changed the U1DLL value...

U1DLL = 78;                   /* 9600 Baud Rate @ 12MHz Clock         */

But still my code is not working...i dont know where i had mistake...

Sorry...My code is working...

This is the code....

#include <LPC23xx.H>
#include <stdio.h>
void delay(int);
int main (void)
{
PINSEL0 |= 0x40000000;                /*  Enable TxD1 in  P0.15   */
PINSEL1 |= 0x00000001;                /*  Enable RxD1 in P0.16   */
U1LCR = 0x83;                         /* 8 bits, no Parity, 1 Stop bit */
U1DLM = 0x00;
U1DLL = 78;                          /* 9600 Baud Rate @ 12MHz Clock */
U1LCR = 0x03;                          /* DLAB = 0 */
U1FCR = 0x07;                          /* enable TX amp RX FIFO ,clears TX amp RX FIFO */

while(1)
{
      U1THR = 'A';
      while (!(U1LSR & 0x20));
}
}

But If i use printf function in my code its not working..May i know why??Below i mentioned the code...

#include <LPC23xx.H>
#include <stdio.h>
void delay(int);
int main (void)
{
PINSEL0 |= 0x40000000;                /*  Enable TxD1 in  P0.15   */
PINSEL1 |= 0x00000001;                /*  Enable RxD1 in P0.16   */
U1LCR = 0x83;                         /* 8 bits, no Parity, 1 Stop bit */
U1DLM = 0x00;
U1DLL = 78;                          /* 9600 Baud Rate @ 12MHz Clock */
U1LCR = 0x03;                          /* DLAB = 0 */
U1FCR = 0x07;                          /* enable TX amp RX FIFO ,clears TX amp RX FIFO */
printf("tesing...");
while(1)
{
      U1THR = 'A';
      while (!(U1LSR & 0x20));
}
}

"But still my code is not working...i dont know where i had mistake..."

But what would happen if you instead wrote:

enum {
    PCLK_UART1 = 12000000    // Note that the different peripherials can have different PCLK
};

...


U1DLL = (PCLK_UART1 / 9600 + 8) / 16;  // +8 to round to nearest instead of truncating answer

That also gives the value 78, but you let the compiler perform the computation for you, and you will still get a correct baudrate if you later change PCLK_UART1 to another frequency. And a reader would be able to see how you computed your baudrate instead of just seeing a magic value 78.

If you want to, you can ignore the fractional baudrate divider register since you have a low-enough baudrate that you get quite a good baudrate match without it.

Did you check your '&&' in the while statement?

And remember - I have not spent any time trying to follow up all your individual bits you set in the different registers. And which order you do it.

And you say "isn't working" but not in what way. Don't you get any data at all on the serial port? Not even a single character? Some bit output but with wrong baudrate?

What do you expect printf() to do? Note that for an embedded product, there are no automatic "correct" behaviour for printf(). If you want printf() to send data to a specific serial port, you can do that.

On the other hand - if printf() is directed to send characters to uart1, then your while loop can't assume that U1THR is directly available for receiving more data - you have to consider if you want to test the state of the UART before or after you try to send characters to the port.

Did you check your '&&' in the while statement?

Ya...I have checked that in the while...In the both conditions (that is && and also &) while loop is working fine..But i am using bitwise AND(&) only....

Using printf: Actually i have to read the port values and have to display in the serail port like..

for example..

temp = FIO1SET0;
printf("port value = %x",temp);

that's why i need the printf function also in my code only for testing purpose only....

See now my code is workig....as i already posted in my previous post...please see that..

this is my code...I am sending a char 'A' continously in serial port...

#include <LPC23xx.H>
#include <stdio.h>
void delay(int);
int main (void)
{
PINSEL0 |= 0x40000000;                /*  Enable TxD1 in  P0.15   */
PINSEL1 |= 0x00000001;                /*  Enable RxD1 in P0.16   */
U1LCR = 0x83;                         /* 8 bits, no Parity, 1 Stop bit */
U1DLM = 0x00;
U1DLL = 78;                          /* 9600 Baud Rate @ 12MHz Clock */
U1LCR = 0x03;                          /* DLAB = 0 */
U1FCR = 0x07;                          /* enable TX amp RX FIFO ,clears TX amp RX FIFO */

while(1)
{
      U1THR = 'A';
      while (!(U1LSR & 0x20));
}
}

To implement printf you need to provide the low-level definitions for the c library functions that printf uses.

Here is a simple example for uart:

void uart_write_char(uint8_t byte)
{
    while ((U0LSR & TX_HOLDING_REG_EMPTY) == 0 );
    U0THR = byte;
}

uint8_t uart_read_char(void)
{
    while ((U0LSR & RX_DATA_READY) == 0);
    return (uint8_t)U0RBR;
}

//*************************************************************
//
// C Lib - LOW-LEVEL CHARACTER INPUT AND OUTPUT
//
//*************************************************************

struct __FILE
{
  int handle;
};

/* FILE is typedef’d in stdio.h. */

FILE __stdout;
FILE __stdin;
FILE __stderr;

int fgetc(FILE *f)
{
    /* Your implementation of fgetc(). */
    return uart_read_char();
};
int fputc(int ch, FILE *stream)
{
    uart_write_char((uint8_t)ch);
    return ch;
}

int ferror(FILE *stream)
{
    /* Your implementation of ferror(). */
    return 0;
}
long int ftell(FILE *stream)
{
    /* Your implementation of ferror(). */
    return 0;
}
int fclose(FILE *f)
{
    /* Your implementation of ferror(). */
    return 0;
}
int fseek(FILE *f, long nPos, int nMode)
{
    /* Your implementation of ferror(). */
    return 0;
}
int fflush(FILE *f)
{
    /* Your implementation of ferror(). */
    return 0;
}

Hope this helps...