[SOLVED] Problem,RTC value send in to UART3 in lpc 1768

[arunbharathi.arasu]

hi,
i have problem to send RTC value in to UART3 inLPC1768,
i can send welcome message in to UART3,but i can't read and send RTC value to UART3.
i don't know where the problem is.

can any one help me.....

Thanks in Advance...

 

[jayanth.devarayanadurga]

I know where the problem is. It is in the code and/or circuit which you have not posted.

 

[mathespbe]

Post your code...

 

[arunbharathi.arasu]

the below code is Real Time Clock with UART3 in lpc 1768.
Required:In Terminal after welcome message if i press any key RTC time will display.
I got welcome message correctly but if i press any key i get number of dots.

/*
#ifdef __USE_CMSIS
#include "LPC17xx.h"
#endif
#include "type.h"
#include "uart.h"
#include <string.h>
#include "rtc.h"



volatile uint32_t UART3Status;
volatile uint8_t  UART3TxEmpty=1;
volatile uint8_t  UART3Buffer[BUFSIZE];
volatile uint32_t UART3Count = 0;



extern volatile uint32_t alarm_on;
RTCTime local_time, alarm_time, current_time;


void UART3_IRQHandler (void)
{
  uint8_t IIRValue, LSRValue;
  uint8_t Dummy = Dummy;

  IIRValue = LPC_UART3->IIR;

  IIRValue >>= 1;			/* skip pending bit in IIR */
  IIRValue &= 0x07;			/* check bit 1~3, interrupt identification */
  if ( IIRValue == IIR_RLS )		/* Receive Line Status */
  {
	LSRValue = LPC_UART3->LSR;
	/* Receive Line Status */
	if ( LSRValue & (LSR_OE|LSR_PE|LSR_FE|LSR_RXFE|LSR_BI) )
	{
	  /* There are errors or break interrupt */
	  /* Read LSR will clear the interrupt */
	  UART3Status = LSRValue;
	  Dummy = LPC_UART3->RBR;		/* Dummy read on RX to clear
							interrupt, then bail out */
	  return;
	}
	if ( LSRValue & LSR_RDR )	/* Receive Data Ready */
	{
	  /* If no error on RLS, normal ready, save into the data buffer. */
	  /* Note: read RBR will clear the interrupt */
	 UART3Buffer[UART3Count] = LPC_UART3->RBR;
	  UART3Count++;
	  if ( UART3Count == BUFSIZE )
	  {
		UART3Count = 0;		/* buffer overflow */
	  }
	}
  }
  else if ( IIRValue == IIR_RDA )	/* Receive Data Available */
  {
	/* Receive Data Available */
	UART3Buffer[UART3Count] = LPC_UART3->RBR;
	UART3Count++;
	if ( UART3Count == BUFSIZE )
	{
	  UART3Count = 0;		/* buffer overflow */
	}
  }
  else if ( IIRValue == IIR_CTI )	/* Character timeout indicator */
  {
	/* Character Time-out indicator */
	UART3Status |= 0x100;		/* Bit 9 as the CTI error */
  }
  else if ( IIRValue == IIR_THRE )	/* THRE, transmit holding register empty */
  {
	/* THRE interrupt */
	LSRValue = LPC_UART3->LSR;		/* Check status in the LSR to see if
									valid data in U0THR or not */
	if ( LSRValue & LSR_THRE )
	{
	  UART3TxEmpty = 1;
	}
	else
	{
	  UART3TxEmpty = 0;
	}
  }
}

uint32_t UARTInit(uint32_t baudrate )
{
  uint32_t Fdiv;
  uint32_t pclkdiv, pclk;
	  LPC_PINCON->PINSEL0 &= ~0x0000000F;
	  LPC_PINCON->PINSEL0 |=  0x0000000A;  /* RxD3 is P0.1 and TxD3 is P0.0 */
	  LPC_SC->PCONP |= 1<<4 | 1<<25; //Enable PCUART1
	  /* By default, the PCLKSELx value is zero, thus, the PCLK for
		all the peripherals is 1/4 of the SystemFrequency. */
	  /* Bit 6~7 is for UART3 */
	  pclkdiv = (LPC_SC->PCLKSEL1 >> 18) & 0x03;
	  switch ( pclkdiv )
	  {
	  case 0x00:
	  default:
		  pclk = SystemCoreClock/4;
		  break;
	  case 0x01:
		  pclk = SystemCoreClock;
		  break;
	  case 0x02:
		  pclk = SystemCoreClock/2;
		  break;
	  case 0x03:
		  pclk = SystemCoreClock/8;
		  break;
	  }
	  LPC_UART3->LCR = 0x83;		/* 8 bits, no Parity, 1 Stop bit */
	  Fdiv = ( pclk / 16 ) / baudrate ;	/*baud rate */
	  LPC_UART3->DLM = Fdiv / 256;
	  LPC_UART3->DLL = Fdiv % 256;
	  LPC_UART3->LCR = 0x03;		/* DLAB = 0 */
	  LPC_UART3->FCR = 0x07;		/* Enable and reset TX and RX FIFO. */

	  NVIC_EnableIRQ(UART3_IRQn);

	  LPC_UART3->IER = IER_RBR | IER_THRE | IER_RLS;	/* Enable UART3 interrupt */
	return (TRUE);
}

void UARTSend(uint8_t *BufferPtr)
{
  while ( *BufferPtr )
    {
	  /* THRE status, contain valid data */
	  while ( !(UART3TxEmpty & 0x01) );
	  LPC_UART3->THR = *BufferPtr;
	  UART3TxEmpty = 0;	/* not empty in the THR until it shifts out */
	  BufferPtr++;
	}
}
void RTCInit( void )
{

  /* Enable CLOCK into RTC */
  LPC_SC->PCONP |= (1 << 9);

  /* If RTC is stopped, clear STOP bit. */
  if ( LPC_RTC->RTC_AUX & (0x1<<4) )
  {
	LPC_RTC->RTC_AUX |= (0x1<<4);
  }

  /*--- Initialize registers ---*/
  LPC_RTC->AMR = 0;
  LPC_RTC->CIIR = 0;
  LPC_RTC->CCR = 0;
  return;
}

void RTCStart( void )
{
  /*--- Start RTC counters ---*/
  LPC_RTC->CCR |= CCR_CLKEN;
  LPC_RTC->ILR = ILR_RTCCIF;
  return;
}
void RTCSetTime( RTCTime Time )
{
  LPC_RTC->SEC = Time.RTC_Sec;
  LPC_RTC->MIN = Time.RTC_Min;
  LPC_RTC->HOUR = Time.RTC_Hour;
  LPC_RTC->DOM = Time.RTC_Mday;
  LPC_RTC->DOW = Time.RTC_Wday;
  LPC_RTC->DOY = Time.RTC_Yday;
  LPC_RTC->MONTH = Time.RTC_Mon;
  LPC_RTC->YEAR = Time.RTC_Year;
  return;
}

RTCTime RTCGetTime( void )
{
  RTCTime LocalTime;

  LocalTime.RTC_Sec = LPC_RTC->SEC;
  LocalTime.RTC_Min = LPC_RTC->MIN;
  LocalTime.RTC_Hour = LPC_RTC->HOUR;
  LocalTime.RTC_Mday = LPC_RTC->DOM;
  LocalTime.RTC_Wday = LPC_RTC->DOW;
  LocalTime.RTC_Yday = LPC_RTC->DOY;
  LocalTime.RTC_Mon = LPC_RTC->MONTH;
  LocalTime.RTC_Year = LPC_RTC->YEAR;
  return ( LocalTime );
}

int main(void)
{
	const char* msg = "                   HH: MM: SS:   DD: MM: YY:\r";
		const char* welcomeMsg = "Real time clock is:";
		const char* space = "  ";
		const char ascii[] ={'0','1','2','3','4','5','6','7','8','9'};

		UARTInit(9600);	/* baud rate setting */
		UARTSend((uint8_t*)msg);
		UARTSend((uint8_t *)welcomeMsg);

		RTCInit();

			  local_time.RTC_Sec = 0;
			  local_time.RTC_Min = 0;
			  local_time.RTC_Hour = 0;
			  local_time.RTC_Mday = 11;
			  local_time.RTC_Wday = 5;
			  local_time.RTC_Yday = 11;		/* current date 07/12/2006 */
			  local_time.RTC_Mon = 10;
			  local_time.RTC_Year = 2013;
			  RTCSetTime( local_time );		/* Set local time */
			  RTCStart();

			  while(1)
			  {
			  	current_time = RTCGetTime();

				if ( UART3Count != 0 )
				{

					UARTSend((uint8_t *)ascii[current_time.RTC_Hour/10]);
					UARTSend((uint8_t *)ascii[current_time.RTC_Hour%10]);
					UARTSend((uint8_t *)space);
					UARTSend((uint8_t *)ascii[current_time.RTC_Min/10]);
					UARTSend((uint8_t *)ascii[current_time.RTC_Min%10]);
					UARTSend((uint8_t *)space);
					UARTSend((uint8_t *)ascii[current_time.RTC_Sec/10]);
					UARTSend((uint8_t *)ascii[current_time.RTC_Sec%10]);
					UARTSend((uint8_t *)space);
					UARTSend((uint8_t *)space);
					UARTSend((uint8_t *)ascii[current_time.RTC_Mday/10]);
					UARTSend((uint8_t *)ascii[current_time.RTC_Mday%10]);
					UARTSend((uint8_t *)space);
					UARTSend((uint8_t *)ascii[current_time.RTC_Mon/10]);
					UARTSend((uint8_t *)ascii[current_time.RTC_Mon%10]);
					UARTSend((uint8_t *)space);
					UARTSend((uint8_t *)ascii[current_time.RTC_Year/1000]);
					UARTSend((uint8_t *)ascii[(current_time.RTC_Year%1000)/100]);
					UARTSend((uint8_t *)ascii[(current_time.RTC_Year%10)/10]);
					UARTSend((uint8_t *)ascii[current_time.RTC_Year%10]);
					}
				UART3Count = 0;
			  }
}

 

[arunbharathi.arasu]

hai jayanth,i posted code,can u find the problem.?

 

[Venkadesh_M]

Hi take care on ISR receiver condition read all the data in the buffer when interrupt coming and why do you pressing any chars is your RTC working fine??

 

[jayanth.devarayanadurga]

I think these should be global as they are constants and they are stored in ROM during compilation.

---

Code C - [expand]
1
2
3
const char* welcomeMsg = "Real time clock is:";
const char* space = "  ";
const char ascii[] ={'0','1','2','3','4','5','6','7','8','9'};

---

I don't know if LPC allows to write to ROM during program run.

 

[arunbharathi.arasu]

hi venkadesh,
Key pressing is just for an Interrupt.After welcome message,if interrupt occurs RTC will display.But i get get special characters and dots.I dont know where the problem is.
above i posted my code can you help me....

- - - Updated - - -

hi jayanth,
That is not a global constant.It is local constant only(i declered inside the main function).

 

[Venkadesh_M]

UARTsend is written to transmit a string but used to display a char...
first assemble all the chars and then send them in a single shot..................

 

[arunbharathi.arasu]

yeah,i got answer.Thanks Venkadesh.

 

[arunbharathi.arasu]

i have one more doubt...
above program time is set by manually.but how can i set system clock.

 

[Venkadesh_M]

you cant do such like when programing but you can set correct time by giving user input when run time like correcting the time in watch...

 

[jayanth.devarayanadurga]

I didn't say it is a global constant. Some compilers like mikroe compilers doesn't allow to define const strings inside functions. They should be declared as global. I don't use LPC. Maybe your compiler allows.

 

[arunbharathi.arasu]

k thanks for you replies...