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 19/11/02 JPP    : Creation
//*----------------------------------------------------------------------------

// Include Standart LIB  files 
#include "eb55.h"
#include "clock_switching.h"

/*-------------------------- External function  -----------------------------*/
extern void usart_asm_irq_handler(void);
extern void mck_clock_speed (short target_source, char frequency_multiplier);

/*--------------------- Internal function prototype -------------------------*/
void Usart_init ( void );

/*---------------------------- Global Variable ------------------------------*/
extern volatile unsigned int  emi_test;
extern unsigned int *ptEmiFlag;
extern unsigned int mck;

/* ------------------------- General constant definition --------------------*/
#define USART_INTERRUPT_LEVEL		2
#define BAUD_RATE			9600

/*---------------------------- Static Variable ------------------------------*/
static const char atmel_header[]=
{
"\n\r  *** ATMEL Clock Switching ***\n\r"
"Copyright (C) 2003 ATMEL Corporations Version: 1.0\n\r"
};

AT91PS_USART COM0;
char message[80];
unsigned int NewVal;
//*-----------------------------------------------------------------------------
//*------------------------- Internal Function --------------------------------
//*-----------------------------------------------------------------------------
//*----------------------------------------------------------------------------
//* Function Name       : at91_scanf
//* Object              : Get a string to USART manage Blackspace and echo
//* Input Parameters    : com descriptor, type string & val return value
//* Output Parameters   : none
//*----------------------------------------------------------------------------
void at91_scanf(AT91PS_USART pUSART ,char * type,unsigned int * val)
{//* Begin
    unsigned int ItFlag =AT91C_US_TIMEOUT | AT91C_US_FRAME | AT91C_US_OVRE |AT91C_US_RXRDY;

    unsigned int read = 0;
    char buff[10];
    unsigned int nb_read =0;

    //* DisableIt USART IT error and RXRDY
    AT91F_US_DisableIt(COM0,ItFlag);

    while( (read != 0x0D) & (nb_read != sizeof(buff)) ) {
        //* wait the USART Ready for reception
	 while((pUSART->US_CSR  & AT91C_US_RXRDY) == 0 ) ;
        //* Get a char
	read = pUSART->US_RHR ;
        buff[nb_read]= (char)read;
        //* Manage Blackspace
        while((pUSART->US_CSR & AT91C_US_TXRDY) ==0)  {}
        if ((char)read == 0x08) {
            if ( nb_read != 0 ) {
              nb_read--;
              pUSART->US_THR = read;
            }
        }
        else {
          //* echo
          pUSART->US_THR = read;
          nb_read++;
        }
    }
    //* scan the value
    sscanf(buff,type,val);
    //* Enable USART IT error and RXRDY
    AT91F_US_EnableIt(COM0,ItFlag);
}//* End

//*----------------------------------------------------------------------------
//* Function Name       : AT91F_USART_Print
//* Object              : This function is used to send a string through the 
//*                       USART channel (Very low level debugging) by polling
//* Input Parameters    : data Pointer 
//* Output Parameters   : none
//*----------------------------------------------------------------------------
void AT91F_USART_Print(
	char *buffer) // \arg pointer to a string ending by \0
{
	while(*buffer != '\0') {
		while (!(COM0->US_CSR & AT91C_US_ENDTX));
		while (!AT91F_US_TxReady(COM0));
		AT91F_US_PutChar(COM0, *buffer++);
	}
}
//*----------------------------------------------------------------------------
//* Function Name       : menu
//* Object              : Usart debug menu
//* Input Parameters    : None
//* Output Parameters   : None
//*----------------------------------------------------------------------------
void menu( char value)	
{
   AT91PS_APMC pAPMC = AT91C_BASE_APMC;

   switch (value) {
	case '1':
	sprintf(message, "Internal clock =  %d \n\r",mck);
	AT91F_USART_Print((char *)&message);
	sprintf(message, "Peripheral\n\r APMC PCSR=0x%08X \n\r", pAPMC->APMC_PCSR) ;
	AT91F_USART_Print((char *)&message);
	sprintf(message, "Clock\n\rAPMCCGMR=0x%08X \n\r",pAPMC->APMC_CGMR);
	AT91F_USART_Print((char *)&message);
	sprintf(message, "APMC SR=  0x%08X \n\r",pAPMC->APMC_SR);
	AT91F_USART_Print((char *)&message);
	AT91F_USART_Print("Work in ");
	if (emi_test==0) AT91F_USART_Print("External\n\r"); else AT91F_USART_Print("Internal\n\r");
	break;
	case '2':
		AT91F_USART_Print("External\n\r");
		*ptEmiFlag=1;
		emi_test=0;
	break;
	case '3':
		AT91F_USART_Print("Internal\n\r");
		*ptEmiFlag=1;
		emi_test=1;
	break;
	case '4':
		AT91F_USART_Print("Clear Peripheral Clock (USART need mask value 0x4)\n\r");
		NewVal = 0;
		at91_scanf(COM0 ,"%x", &NewVal);
		pAPMC->APMC_PCDR = NewVal;
		sprintf(message, "Peripheral\n\r APMC PCSR=0x%08X \n\r",pAPMC->APMC_PCSR);
		AT91F_USART_Print((char *)&message);
	break;
	case '5':
		AT91F_USART_Print("Set Peripheral Clock\n\r");
		NewVal = 0;
		at91_scanf(COM0 ,"%x", &NewVal);
		sprintf(message, "Peripheral\n\rAPMC PCSR=0x%08X \n\r",pAPMC->APMC_PCSR);
		pAPMC->APMC_PCER = NewVal;
		AT91F_USART_Print((char *)&message);
	break;
	case '6':
		AT91F_USART_Print("Set CGMR Clock\n\r");
		NewVal = 0;
		at91_scanf(COM0 ,"%x", &NewVal);
		sprintf(message, "Peripheral\n\rAT91C_APMC_PCSR=0x%08X \n\r",*AT91C_APMC_PCSR);
		pAPMC->APMC_CGMR = NewVal;
		AT91F_USART_Print((char *)&message);
	break;

	case 'A':
		NewVal = 0;
		sprintf(message, "Internal clock In MHz\n\r");
		AT91F_USART_Print((char *)&message);
		at91_scanf(COM0 ,"%d", &NewVal);
		mck_clock_speed (TO_PLL_OUTPUT,NewVal /(EXTARNAL_CLOCK_Mhz/PRESCALER_VAL) ) ;
		mck= EXT_QUARTZ/EXTARNAL_CLOCK_Mhz * NewVal ;
		// Usart Configure
		Usart_init ();
		sprintf(message, "Internal clock =  %d \n\r",mck);
		AT91F_USART_Print((char *)&message);
	break;

	default:
		AT91F_USART_Print("\n\r");
		break;
	}
}

//*-----------------------------------------------------------------------------
//* --------------------------- 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
		menu ( 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 status 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
{
    unsigned int US_ID = AT91C_ID_US0;
    COM0= AT91C_BASE_US0;

        //* Define RXD and TXD as peripheral Usart 0
        AT91F_PIO_CfgPeriph(AT91C_BASE_PIOA,AT91C_PA16_RXD0 | AT91C_PA15_TXD0,0);

    	// First, enable the clock of the USART
    	AT91F_APMC_EnablePeriphClock ( AT91C_BASE_APMC, 1<<US_ID ) ;
	
	// Usart Configure
	AT91F_US_Configure (COM0, mck,AT91C_US_ASYNC_MODE, BAUD_RATE, 0);
	// Clear Transmit and Receive Counters
	COM0->US_RPR = COM0->US_RCR =0;
	COM0->US_TPR = COM0->US_TCR =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 0 interrupt
	AT91F_AIC_ConfigureIt ( AT91C_BASE_AIC, US_ID, USART_INTERRUPT_LEVEL,AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE, usart_asm_irq_handler); 
	AT91F_AIC_EnableIt (AT91C_BASE_AIC, US_ID); 
	
 	AT91F_US_SendFrame(COM0,(char *)atmel_header,sizeof(atmel_header));
 		
 	//* Send menu 	
	AT91F_USART_Print("1: print info\n\r2:Run in External Memory\n\r3: Run in Internal Memory\n\r4: Set the peripheral lock\n\r5:Set the peripheral lock\n\r6: Change CGMR\n\rA: Set New internal Clock in from 8 to 32 Step 4 Mhz \n\r");

//* End
}