Quality RTOS & Embedded Software

 Real time embedded FreeRTOS RSS feed 
Quick Start Supported MCUs PDF Books Trace Tools Ecosystem TCP & FAT




Loading

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)
{
//---
}
}


[ Back to the top ]    [ About FreeRTOS ]    [ Sitemap ]    [ ]




Copyright (C) Amazon Web Services, Inc. or its affiliates. All rights reserved.

Latest News

FreeRTOS kernel V10 is available for immediate download. Now MIT licensed.


FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

IAR Partner

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

STMicro RTOS partner supporting ARM7, ARM Cortex-M3, ARM Cortex-M4 and ARM Cortex-M0

Texas Instruments MCU Developer Network RTOS partner for ARM and MSP430 microcontrollers

OpenRTOS and SafeRTOS