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I have a problem with lpc2148 uart receiver (with interrupt)

Hello Sir,
when I use lpc2148 UART receiver interrupt then microcontroller is not receiving any value
but if I use a simple receiver then it's working correctly and receive correct data.
I'm check this code on both hardware or proteus simulator but it's not working
this is my interrupt code,

#include <lpc21xx.h>
volatile char x;
void initUart0(void);
void Uart0ISR(void) __irq;
void delay(int time)
{
        int i,j;
        for(i=0;i<time;i++)
          for(j=0;j<1275;i++);
}
int main(void)
{
        IO1DIR = 0xFFFF0000;
        IO0DIR = (1<<3);
        initUart0();
        while(1){
         IO1PIN=x<<16;
                delay(1);
        }
}

void initUart0(void)
{

        PINSEL0|=0x00000005;
        U0LCR = 0x83;
        U0DLM = 0x00;
        U0DLL = 19;
        U0LCR = 0X03;
        U0FCR = 0x01;
        VICVectAddr1 = (unsigned long)Uart0ISR;
        VICVectCntl1 = 0x20 | 6;
        VICIntEnable |= (1<<6);
}

void Uart0ISR(void) __irq
{
         x      = U0RBR;
         IOPIN0 ^=(1<<3);
         VICVectAddr = 0x0;

}

and this is my simple code, it is working on both hardware or software correctly


#include <lpc21xx.h>
volatile char x;
void initUart0(void);
char uartoRec();

void delay(int time)
{
        int i,j;
        for(i=0;i<time;i++)
          for(j=0;j<10275;i++);
}
int main(void)
{
        IO1DIR = 0xFFFF0000;
        initUart0();
        while(1){
                IOPIN1 = uartoRec()<<16;
        }
}

void initUart0(void)
{

        PINSEL0|=0x00000005;
        U0LCR=(1<<7);
  U0DLM = 0x00;
  U0DLL = 19;
        U0LCR=0X03;
}
char uartoRec()
{
        while(!(U0LSR&(0x01)));
        x = U0RBR;
        return x;
}

thank you

Parents

0 Bhura Malik over 8 years ago in reply to edPer Westermark

[modify] LPC2148 UART receiver interrupt code sir, I am added comment in this code, now this modified code is working on proteus but on hardware, it shows the 0xFF value of entered character


#include <lpc214x.h>
volatile long  x;
void initUart0(void);

void delay(int time)   //delay function
{
        int i,j;
        for(i=0;i<time;i++)
          for(j=0;j<10275;j++);
}
void Uart0ISR(void) __irq;
void initClocks(void)
{
        PLL0CON = 0x01;   //Enable PLL
        PLL0CFG = 0x24;   //Multiplier and divider setup
        PLL0FEED = 0xAA;  //Feed sequence
        PLL0FEED = 0x55;

        while(!(PLL0STAT & 0x00000400)); //is locked?

        PLL0CON  = 0x03;   //Connect PLL after PLL is locked
        PLL0FEED = 0xAA;  //Feed sequence
        PLL0FEED = 0x55;
        VPBDIV   = 0x01;    // PCLK is same as CCLK i.e.60 MHz
}
int main(void)
{
        IO0DIR = 0xFF0000;
  initClocks();    //init Clocks
        initUart0();        // init uart0
        while(1){
                IOSET0 = x<<16;  // { ascii value set on IOPIN 16 - IOPIN 23}
                delay(500);
                IOCLR0 = x<<16;  // clear IOPIN
                delay(5);
        }
}

void initUart0(void)
{

        PINSEL0 = 0x5;  /* Select TxD for P0.0 and RxD for P0.1 */
        U0LCR   = 0x83; /* 8 bits, no Parity, 1 Stop bit | DLAB set to 1 */
        U0DLL   = 78;   //baud Rate 9600 at 12MHZ
        U0DLM   = 1;
        U0FDR   = 0xF1; /* MULVAL=15(bits - 7:4) , DIVADDVAL=0(bits - 3:0)*/
        U0LCR &= 0x0F; // Set DLAB=0 to lock MULVAL and DIVADDVAL
        U0IER=0x1;     // Enable RBR interrupt
        VICVectAddr1 = (unsigned long)Uart0ISR;
        VICVectCntl1 = 0x20 | 6;
        VICIntEnable |= (1<<6);
        //BaudRate is now ~9600 and we are ready for UART communication!
}
void Uart0ISR(void) __irq
{
        long int regVal;
        regVal = U0IIR;
         x      = U0RBR;     //read data
         VICVectAddr = 0x0;

}/*
char uartoRec()
{
        while(!(U0LSR&(0x01)));
        x = U0RBR;
        return x;
}
*/

Reply

0 Bhura Malik over 8 years ago in reply to edPer Westermark

[modify] LPC2148 UART receiver interrupt code sir, I am added comment in this code, now this modified code is working on proteus but on hardware, it shows the 0xFF value of entered character


#include <lpc214x.h>
volatile long  x;
void initUart0(void);

void delay(int time)   //delay function
{
        int i,j;
        for(i=0;i<time;i++)
          for(j=0;j<10275;j++);
}
void Uart0ISR(void) __irq;
void initClocks(void)
{
        PLL0CON = 0x01;   //Enable PLL
        PLL0CFG = 0x24;   //Multiplier and divider setup
        PLL0FEED = 0xAA;  //Feed sequence
        PLL0FEED = 0x55;

        while(!(PLL0STAT & 0x00000400)); //is locked?

        PLL0CON  = 0x03;   //Connect PLL after PLL is locked
        PLL0FEED = 0xAA;  //Feed sequence
        PLL0FEED = 0x55;
        VPBDIV   = 0x01;    // PCLK is same as CCLK i.e.60 MHz
}
int main(void)
{
        IO0DIR = 0xFF0000;
  initClocks();    //init Clocks
        initUart0();        // init uart0
        while(1){
                IOSET0 = x<<16;  // { ascii value set on IOPIN 16 - IOPIN 23}
                delay(500);
                IOCLR0 = x<<16;  // clear IOPIN
                delay(5);
        }
}

void initUart0(void)
{

        PINSEL0 = 0x5;  /* Select TxD for P0.0 and RxD for P0.1 */
        U0LCR   = 0x83; /* 8 bits, no Parity, 1 Stop bit | DLAB set to 1 */
        U0DLL   = 78;   //baud Rate 9600 at 12MHZ
        U0DLM   = 1;
        U0FDR   = 0xF1; /* MULVAL=15(bits - 7:4) , DIVADDVAL=0(bits - 3:0)*/
        U0LCR &= 0x0F; // Set DLAB=0 to lock MULVAL and DIVADDVAL
        U0IER=0x1;     // Enable RBR interrupt
        VICVectAddr1 = (unsigned long)Uart0ISR;
        VICVectCntl1 = 0x20 | 6;
        VICIntEnable |= (1<<6);
        //BaudRate is now ~9600 and we are ready for UART communication!
}
void Uart0ISR(void) __irq
{
        long int regVal;
        regVal = U0IIR;
         x      = U0RBR;     //read data
         VICVectAddr = 0x0;

}/*
char uartoRec()
{
        while(!(U0LSR&(0x01)));
        x = U0RBR;
        return x;
}
*/

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