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Problem UART Interrupt LPC2134

Question asked by Roberto Rober on Jul 9, 2016
Latest reply on Jul 28, 2016 by Roberto Rober

First hello to everyone.

Sorry for my English.

I tell you.

I'm starting to use microcontrollers ARM7 specifically the LPC2134 and I am performing a bidirectional serial communication.

The program consists blink an LED to verify that the system is working, and UART communication with a PC and a serial adapter to convert levels.

My purpose is to use a vectored IRQ interrupt, so that when some data arrives the program stops and observe the interrupt and save the received data in an array for later processing.

In addition I make a bluque sending the ASCII table to the PC.

My problem is that encuanto recivo a data interruption jumps and I can not in any way out of it by staying in an infinite loop in the interruption.

The program I'm doing with the KEIL 4.


Main Program

int main()



    VICIntEnClr=0xFFFF;//Borro cualquier posible interrupcion




    while (1)




           LED_blink ();//Parpadeo del LED







void init_uart(void)



    U0FDR=0x10;//Multivall a 1

    U0LCR|=BIT7;//Activo Bit DLAB para poder configurar velocidad        

    U0DLL=divisor & 0xFF;

    U0DLM = (divisor >> 8) & 0xFF;

    U0LCR &=~BIT7;//Borro Bit DLAB para poder configurar velocidad        

    U0FCR=1;//Activo FIFO        

    U0IER = 0;//Desabilito interrupciones UART 1


    VICIntSelect &= ~(1<<UART_0);

    VICDefVectAddr |= (1<<UART_0);

    VICVectCntl10 = 0x20 | UART_0;                     /* Prioridad 0 Vectorizada use it for UART 0 Interrupt*/

    VICVectAddr10 = (unsigned long)RX_UART_CERO ;           /* set interrupt vector in 0   */

    VICIntEnable |= BIT6;                   /* Enable UART0 Interrupt     */

    U0IER = 1;//Habilito interrupcion de recepcion de datos validos




_irq void RX_UART_CERO (void)


   if(U0IIR&DR)      // Infinite loop


      while (!(U0LSR&DR));









   VICVectAddr &= 0x0000;//Clear Flag Interrupts but not exit and return to Infinite loop                               



Everything works fine until you receive date UART in the LPC. Then jumps to the interruption and there does not come out.

No longer what to do, I take several days reading the datasheet and reviewing the program, but can not find anything wrong.

I request help from someone who can guide me to solve the problem and continue learning.


Thanks you very much.