led.c

来自「S3C4510(ARM7)开发板bootloader实现及板载硬件测试代码」· C语言 代码 · 共 87 行

#include "led.h"

static void delay(int x)
{
	int i;
	while (x--)
	{
		for (i = 65536  ; i > 0; i--);		
	}	
}

void led (int bit, int val)
{
	int led_mask[LED_NUM] = {0x00000040, 0x00000020, 0x00000010, 0x00020000};
	static int led_init_done = 0;
	
	if (bit > LED_NUM - 1 || bit < 0 || (val != 0)&&(val != 1))
		return;		
		
	if (!led_init_done)
	{
		IOPMOD |= 0x00020070;
		IOPDATA &= (~0x00020070);	
		led_init_done = 1;
	}
	
	IOPDATA = val ? (IOPDATA | led_mask[bit]) : (IOPDATA & (~led_mask[bit]));
}

void led_set_val(int val)
{
	int i;
	int bit[LED_NUM];
	int led_mask[LED_NUM] = {0x00000040, 0x00000020, 0x00000010, 0x00020000};
	static int led_init_done = 0;

	if (val > 15)
		return;
		
	if (!led_init_done)
		{
			IOPMOD |= 0x00020070;
			IOPDATA &= (~0x00020070);	
			led_init_done = 1;
		}
		
	/* bit[o] -> IO17; bit[1] -> IO4; bit[2] -> IO5; bit[3] -> IO6 */
	for (i = 0; i < LED_NUM; i++)
	{
		bit[i] = val & (0x01 << i);
		IOPDATA = bit[i] ? (IOPDATA | led_mask[i]) : (IOPDATA & (~led_mask[i]));
	}
}

void ledblink( void )
{	
		int i;
	
		for (i = 0; i < LED_NUM; i++)
		{
			led(i, 1);
			delay( 20 );
			led(i, 0);
		}
		
		for (i = 0; i < LED_NUM; i++)
		{
			led(i, 1);
		}
		delay( 30 );
		
		for (i = 0; i < LED_NUM; i++)
		{
			led(i, 0);
		}
		delay( 20 );
		
		for (; i > 0; i--)
		{
			led(i, 1);
			delay( 20 );
			led(i, 0);
		}
}