rt-thread/bsp/lpc2148/drivers/board.c

/*
 * File      : board.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006, RT-Thread Develop Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://openlab.rt-thread.com/license/LICENSE
 *
 * Change Logs:
 * Date           Author       Notes
 * 2006-08-23     Bernard      first implementation
 */

#include <rthw.h>
#include <rtthread.h>

#include "lpc214x.h"
#include "board.h"

/**
 * @addtogroup LPC2148
 */
/*@{*/

/**
 * This is the timer interrupt service routine.
 * @param vector the irq number for timer
 */
void rt_hw_timer_handler(int vector, void *param)
{
	rt_tick_increase();

	/* clear interrupt flag */
	T0IR |= 0x01;

	/* acknowledge Interrupt */
	VICVectAddr = 0;
}

/**
 * This function is used to display a string on console, normally, it's
 * invoked by rt_kprintf
 *
 * @param str the displayed string
 */
void rt_hw_console_output(const char* str)
{
	while (*str)
	{
		if (*str=='\n')
		{
			while (!(U0LSR & 0x20));
			U0THR = '\r';
		}

		while (!(U0LSR & 0x20));
		U0THR = *str;

		str ++;
	}
}

#define BAUD_RATE	115200
#define U0PINS		0x05
void rt_hw_console_init()
{
	/* Enable RxD and TxD pins */
  	PINSEL0 = U0PINS;

	/* 8 bits, no Parity, 1 Stop bit */
	U0LCR = 0x83;

	/* Setup Baudrate */
	U0DLL = (PCLK/16/BAUD_RATE) & 0xFF;
	U0DLM = ((PCLK/16/BAUD_RATE) >> 8) & 0xFF;

	/* DLAB = 0 */
	U0LCR = 0x03;
}

/**
 * This function will initial sam7x256 board.
 */
void rt_hw_board_init(void)
{
	/* console init */
	rt_hw_console_init();

	/* prescaler = 0*/
   	T0PR = 0;
   	T0PC = 0;

	/* reset and enable MR0 interrupt */
	T0MCR = 0x3;
	T0MR0 = PCLK / RT_TICK_PER_SECOND;

	/* enable timer 0 */
	T0TCR = 1;

	/* install timer handler */
	rt_hw_interrupt_install(TIMER0_INT, rt_hw_timer_handler, RT_NULL, "TIMER0");
	rt_hw_interrupt_umask(TIMER0_INT);
}

/*@}*/