LED doesnt turn ON (or OFF)

Using Arduino Programming Questions
9

pylon:
Show us the whole code you are using because you have changed some things (the definition of the LED which was fine in the original code but wrong defined to 13).

This code is not intended for the Arduino IDE, it's AVR C code to be compiled directly by the gcc-avr.

Here is my latest code:

#include <stdio.h>
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>

#define LED 6 // LED is on Pin 13 or Pin 5 of Port B
/*
 * UART-Initialization from www.mikrocontroller.net
 * Hint: They are awesome! :-)
 */

#ifndef F_CPU
#warning "F_CPU was not defined, defining it now as 16000000"
#define F_CPU 16000000UL
#endif

#define BAUD 9600UL      // baud rate
// Calculations
#define UBRR_VAL ((F_CPU+BAUD*8)/(BAUD*16)-1)   // smart rounding
#define BAUD_REAL (F_CPU/(16*(UBRR_VAL+1)))     // real baud rate
#define BAUD_ERROR ((BAUD_REAL*1000)/BAUD) // error in parts per mill, 1000 = no error
#if ((BAUD_ERROR<990) || (BAUD_ERROR>1010))
#error Error in baud rate greater than 1%!
#endif

void uart_init(void) {
	UBRR0H = UBRR_VAL >> 8;
	UBRR0L = UBRR_VAL & 0xFF;

	UCSR0C = (0 << UMSEL01) | (0 << UMSEL00) | (1 << UCSZ01) | (1 << UCSZ00); // asynchron 8N1
	UCSR0B |= (1 << RXEN0); // enable UART RX
	UCSR0B |= (1 << TXEN0); // enable UART TX
	UCSR0B |= (1 << RXCIE0); //interrupt enable
}

/* Receive symbol, not necessary for this example, using interrupt instead*/
uint8_t uart_getc(void) {
	while (!(UCSR0A & (1 << RXC0)))
		// wait until symbol is ready
		;
	return UDR0; // return symbol
}

uint8_t uart_putc(unsigned char data) {
	/* Wait for empty transmit buffer */
	while (!(UCSR0A & (1 << UDRE0)))
		;
	/* Put data into buffer, sends the data */
	UDR0 = data;
	return 0;
}


void initIO(void) {
	DDRD |= (1 << DDD3);
	DDRB = 0xff; //all out
}


volatile uint8_t data = 10;

int main(void) {
	initIO();
	uart_init();
	sei();

	uint8_t i = 0;
	volatile uint8_t pause;
	for(;;) {
		pause = data;
		PORTB &= (1 << LED);
		for(i = 0; i < pause; i++)
			_delay_us(10000);
		PORTB |= ~(1 << LED);
		for(i = 0; i < pause; i++)
			_delay_us(10000);
	}
	return 0; // never reached
}

ISR(USART_RX_vect) {//attention to the name and argument here, won't work otherwise
	data = UDR0;//UDR0 needs to be read
}

And it is blinking.

But if I change the _delay_us function to delay(1000):

for(;;) {
		pause = data;
		PORTB &= (1 << LED);
		delay(1000);
		PORTB |= ~(1 << LED);
		delay(1000);
	}

It stops blinking, it just keep turned ON.