AT91SAM7SE512: USART0 RXD interrupt

Posted by nanjooh on October 19, 2007
Dear All,

I am using the Keil uvision3 ARM version(Real view),
In my code i am using UART0 for Transmission and reception.

The transmission has no problem. For reception i am using the RX interrupt.
The problem is, If i type any letter in the keyboard (Hyperterminal),
no receiver interrupt is generated in the controller.

Can you please help me to rectify this problem.

operating system: XP
Operating Tool : Keil Uvision3 ARM view (version 3.53)
Controller: AT91SAM7SE512
For your reference here is the code,

//*----------------------------------------------------------------------------
//* Function Name : Usart_c_irq_handler
//* Object : C handler interrupt function call by the interrupts
//* assembling routine
//*----------------------------------------------------------------------------
void Usart_c_irq_handler(void)
{
AT91PS_USART USART_pt = AT91C_BASE_US0;
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
//*----------------------------------------------------------------------------
void Usart_init ( void )
//* Begin
{

AT91PS_USART COM0 = AT91C_BASE_US0;

//* Configure PIO controllers to periph mode
AT91F_PIO_CfgPeriph( AT91C_BASE_PIOA,
((unsigned int) AT91C_PA5_RXD0 ) |
((unsigned int) AT91C_PA6_TXD0 ), 0); // Peripheral B
//((unsigned int) AT91C_PA7_RTS0 ) |
//((unsigned int) AT91C_PA8_CTS0 ), // Peripheral A
//0); // Peripheral B

//* First, enable the clock of the USART
AT91F_PMC_EnablePeriphClock ( AT91C_BASE_PMC, 1 << AT91C_ID_US0 ) ;
//* Usart Configure
AT91F_US_Configure (COM0, AT91B_MCK, AT91C_US_ASYNC_MODE, AT91_BAUD_RATE, 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_US0, USART_INTERRUPT_LEVEL,AT91C_AIC_SRCTYPE_HIGH_LEVEL, Usart_c_irq_handler);
AT91F_AIC_EnableIt (AT91C_BASE_AIC, AT91C_ID_US0);

AT91F_US_PutChar (COM0,'X');

AT91F_US_SendFrame(COM0,(char *)display,sizeof(display),0,0);



//* End
}


with regards,
Murthy.R


RE: AT91SAM7SE512: USART0 RXD interrupt

Posted by Allure99 on October 19, 2007
Do you have your interrupt service routine?

serialISR.c ?

void vUART_ISR( void ) __attribute__ ((naked));

void vUART_ISR( void )
{
if( ulStatus & AT91C_US_RXRDY)
{
//---
}
}