bo_load.c

ARM入门的好帮手.包含了从简单到相对较复杂的程序.

//*----------------------------------------------------------------------------
//*      ATMEL Microcontroller Software Support  -  ROUSSET  -
//*----------------------------------------------------------------------------
//* The software is delivered "AS IS" without warranty or condition of any
//* kind, either express, implied or statutory. This includes without
//* limitation any warranty or condition with respect to merchantability or
//* fitness for any particular purpose, or against the infringements of
//* intellectual property rights of others.
//*----------------------------------------------------------------------------
//* File Name           : bo_load.c
//* Object              : Load program in RAM
//*	
//* Imported resources  : 
//* Exported resources  : BootLoad
//*
//* 1.0  18/07/00  PF   : Creation
//* 1.1  29/01/02  PFi	: Clean up. The include of <stdio.h> has been removed.
//*----------------------------------------------------------------------------
#include "periph\stdc\std_c.h"
#include "parts\m55800\lib_m55800.h"
#include "periph\usart\lib_usart.h"
#include "periph\pio\lib_pio.h"
#include "targets\eb55\eb55.h"

/* Hardware description */
#define NB_USART    	2
#define PIO_IRQ0    	9

#define SSRAM_ADDR  	0x02000000
#define BUFFER_SIZE 	0x0FFFF
#define	SW134_MASK		(0x1A<<16)

/* ------------------------ */
/* USART BAUD RATE			*/
/* ------------------------ */
#define BD_115200       (32000000 / (16 * 115200))		/* CD = 0x11 */

//*----------------------------------------------------------------------------------
//* Function Name       : BootLoad
//* Object              : Main function of the bootloader
//* Input Parameters    : none
//* Output Parameters   : none
//* Functions called    : at91_usart_open, at91_usart_receive_frame
//*						: at91_usart_get_status, at91_usart_close
//*----------------------------------------------------------------------------------
u_int BootLoad ( void )
//* Begin
{
	u_int	end ;
	
	StructUSART		*usart0_pt = USART0_BASE ;
	StructUSART		*usart1_pt = USART1_BASE ;	
	
    //* Open USART 0 and initialize PDC Reception
	at91_usart_open  ( &USART0_DESC , US_ASYNC_MODE , BD_115200 , 0x0 ) ;
	at91_usart_receive_frame ( &USART0_DESC, (char *)SSRAM_ADDR, BUFFER_SIZE , 0 ) ;
		
	//* Open USART 1 and initialize PDC Reception
	at91_usart_open  ( &USART1_DESC , US_ASYNC_MODE , BD_115200 , 0x0 ) ;
	at91_usart_receive_frame ( &USART1_DESC, (char *)SSRAM_ADDR, BUFFER_SIZE , 0 ) ;
		
    //* Wait for any button pushed
	end = FALSE ;
    while ( !end )
	{ 
		//* If Any button pressed, Exit from SRAM Loader 
		if (((at91_pio_read(&PIOB_DESC)& SW134_MASK) !=SW134_MASK) || ((at91_pio_read(&PIOA_DESC)& SW2_MASK)!=SW2_MASK))
			end = TRUE ;

		//* Test the End of receive for USART0
		if (( at91_usart_get_status ( &USART0_DESC ) & US_ENDRX ) != 0 )
		{
			usart0_pt->US_RCR = BUFFER_SIZE ;
		}

		//* Test the End of receive for USART1
		if (( at91_usart_get_status ( &USART1_DESC ) & US_ENDRX ) != 0 )
		{
			usart1_pt->US_RCR = BUFFER_SIZE ;
		}
	}

	//* Close USART 0 and USART 1
	at91_usart_close ( &USART0_DESC ) ;
	at91_usart_close ( &USART1_DESC ) ;

	at91_pio_write (&PIOB_DESC, LED2, LED_OFF) ;

	return ( SSRAM_ADDR ) ;
}