interrupt_usart.c

ATMEL AT91RM9200开发板配套光盘上的全部示例程序

//*----------------------------------------------------------------------------
//*      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           : interrupt_Usart.c
//* Object              : USART Interrupt Management
//*
//* 1.0 03/Jan/03 JPP   : Creation
//*----------------------------------------------------------------------------

// Include Standard LIB  files 
#include "include/AT91R40008.h"
#include "include/lib_AT91R40008.h"
#include "eb40A.h"

extern void usart_asm_irq_handler(void);
#define USART_INTERRUPT_LEVEL		7

static const char atmel_header[]=
{
"\n\r  *** ATMEL Usart IRQ ***\n\r"
"Copyright (C) 2002 ATMEL Corporations Version: 1.0\n\r"
};


#define AT91C_US_USMODE_NORMAL	AT91C_US_CHMODE_NORMAL
//*------------------------- Internal Function --------------------------------
//*------------------------- Interrupt Function -------------------------------

//*----------------------------------------------------------------------------
//* Function Name       : Usart_c_irq_handler
//* Object              : C handler interrupt function called by the interrupts 
//*                       assembling routine
//* Input Parameters    : <RTC_pt> time rtc descriptor
//* Output Parameters   : increment count_timer0_interrupt
//*----------------------------------------------------------------------------
void Usart_c_irq_handler(AT91PS_USART USART_pt)
{
	unsigned int status;
	//* get Usart status register
	status = USART_pt->US_CSR;
	if ( status & AT91C_US_RXRDY){
		//* Get byte and send
		AT91F_US_PutChar (USART_pt, AT91F_US_GetChar(USART_pt));
	}
	
	if ( status & AT91C_US_OVRE) {
		//* clear US_RXRDY
		 AT91F_US_GetChar(USART_pt);
		 AT91F_US_PutChar (USART_pt, 'O');
	}

	//* Check error
	if ( status & AT91C_US_PARE) {
		 AT91F_US_PutChar (USART_pt, 'P');
	}

	if ( status & AT91C_US_FRAME) {
		 AT91F_US_PutChar (USART_pt, 'F');
	}

	if ( status & AT91C_US_TIMEOUT){
		USART_pt->US_CR = AT91C_US_STTTO;
		 AT91F_US_PutChar (USART_pt, 'T');
	}

	//* Reset the satus bit
	 USART_pt->US_CR = AT91C_US_RSTSTA;
}
//*-------------------------- External Function -------------------------------

//*----------------------------------------------------------------------------
//* Function Name       : Usart_init
//* Object              : USART initialization 
//* Input Parameters    : none
//* Output Parameters   : TRUE
//*----------------------------------------------------------------------------
void Usart_init ( void )
//* Begin
{
	AT91PS_USART COM0;
	
	COM0= AT91C_BASE_US1;

        //* Define RXD and TXD as peripheral
        AT91F_PIO_CfgPeriph(AT91C_BASE_PIO,AT91C_P22_RXD1 | AT91C_P21_TXD1,0);

    	// First, enable the clock of the PIOB
    	AT91F_PS_EnablePeriphClock ( AT91C_BASE_PS, 1<<AT91C_ID_US1 ) ;
	
	// Usart Configure
	AT91F_US_Configure (COM0, MCK,AT91C_US_ASYNC_MODE, 38400, 0);
	
	// Enable usart 
	COM0->US_CR = AT91C_US_RXEN | AT91C_US_TXEN;
    	
    	//* Enable USART IT error and RXRDY
    	AT91F_US_EnableIt(COM0,AT91C_US_TIMEOUT | AT91C_US_FRAME | AT91C_US_OVRE |AT91C_US_RXRDY);

    	//* open Usart 1 interrupt
	AT91F_AIC_ConfigureIt ( AT91C_BASE_AIC, AT91C_ID_US1, USART_INTERRUPT_LEVEL,AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE, usart_asm_irq_handler); 
	AT91F_AIC_EnableIt (AT91C_BASE_AIC, AT91C_ID_US1); 
	
	AT91F_US_PutChar (COM0,'X');
	
 	AT91F_US_SendFrame(COM0,(char *)atmel_header,sizeof(atmel_header));
 	
	
//* End
}