Lpc2000

I'm trying to learn how to write C programs for my LPC-MT-2106 board 
from Olimex.  I'm using the GNU toolchain for compiling/linking and 
CrossWorks for programming the board.  I successfully got the LED to 
blink; however, as soon as I introduced a function call, my code 
won't work.  It still compiles/links/programs just fine, but the LED 
won't change.  It seems like the processor never returns from any 
function calls.  Any ideas why this may be?

I've included my code and makefile below.  The first program works 
and the second one doesn't.

Thanks in advance!

Thomas



// led.c without function calls

/* General Purpose Input/Output (GPIO) */
#define IOPIN	(*((volatile unsigned long *) 0xE0028000))
#define IOSET	(*((volatile unsigned long *) 0xE0028004))
#define IODIR	(*((volatile unsigned long *) 0xE0028008))	// 0-
INPUT 1-OUTPUT
#define IOCLR	(*((volatile unsigned long *) 0xE002800C))

#define LEDMASK 0x00001000	// LED	P0.12

unsigned int i;

int main()
{
	IODIR = IODIR | LEDMASK;
	while(1)
	{
		IOCLR = IOCLR | LEDMASK;
		for( i = 0; i < 50000; i++ )
		{
		}
		IOSET = IOSET | LEDMASK;
		for( i = 0; i < 50000; i++ )
		{
		}
	}
	return 0;
}
// EOF


// led.c with a function call

/* General Purpose Input/Output (GPIO) */
#define IOPIN	(*((volatile unsigned long *) 0xE0028000))
#define IOSET	(*((volatile unsigned long *) 0xE0028004))
#define IODIR	(*((volatile unsigned long *) 0xE0028008))	// 0-
INPUT 1-OUTPUT
#define IOCLR	(*((volatile unsigned long *) 0xE002800C))


#define LEDMASK 0x00001000	// LED	P0.12

void delay( unsigned int i )
{
	for( i = 0; i < 50000; i++ )
	{
	}
}

int main()
{
	IODIR = IODIR | LEDMASK;
	while(1)
	{
		IOCLR = IOCLR | LEDMASK;
		delay( 50000 );
		IOSET = IOSET | LEDMASK;
		delay( 50000 );
	}
	return 0;
}
// EOF


// makefile

arm-elf-gcc -c led.c -o led.o
arm-elf-gcc -TLPCH40MB.LD -nostartfiles -o led.elf led.o