nid help on LED blinking

i have problem with the led blinking. I using the exmaple program given by keil using uVision3. When i run the program, the LED on the development board didnt blink, it just stay on! wat should i do?

thanks!

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  • my code:

    /* BLINKY.C - LED Flasher for the Keil MCBx51 Evaluation Board with 80C51 device*/
    
    #include <REG8252.H>
    
    
    // When you have enabled the option Stop Program Execution with Serial
    // Interrupt, the Monitor-51 uses the serial interrupt of the UART.
    // It is therefore required to reserve the memory locations for the interrupt
    // vector.  You can do this by adding one of the following code lines:
    
    // char code reserve [3] _at_ 0x23;   // when using on-chip UART for communication
    // char code reserve [3] _at_  0x3;   // when using off-chip UART for communication
    
    void wait (void)  {                   /* wait function */
      ;                                   /* only to delay for LED flashes */
    }
    
    void main (void)  {
      unsigned int i;                     /* Delay var */
      unsigned char j;                    /* LED var */
    
      while (1) {                         /* Loop forever */
        for (j=0x01; j< 0x80; j<<=1)  {   /* Blink LED 0, 1, 2, 3, 4, 5, 6 */
          P1 = j;
                                /* Output to LED Port */
          for (i = 0; i < 10000; i++)  {  /* Delay for 10000 Counts */
           wait ();                       /* call wait function */
          }
        }
    
        for (j=0x80; j> 0x01; j>>=1)  {   /* Blink LED 6, 5, 4, 3, 2, 1 */
          P1 = j;                         /* Output to LED Port */
          for (i = 0; i < 10000; i++)  {  /* Delay for 10000 Counts */
           wait ();                       /* call wait function */
          }
        }
      }
    }
    

    i not sure whether to use port 0 or 1, but i have tried using both port and it still wont blink. Hope you guys can help me thanks alot!

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