Quality RTOS & Embedded Software

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




Loading

Using ISR-wrapping with PIO

Posted by Nobody/Anonymous on May 10, 2005
Hello!

I am having problems to get the ISR-handler for PIO to work . The interrupt is called properly but when processor is about to leave the ISR I get a data abort when portRESTORE_CONTEXT is called. I can't figure out why!! ???

My code follows:

__arm void pio_ISR( void )
{
portCHAR cContextSwitchRequired;

int dummy;
dummy = AT91C_BASE_PIOA->PIO_ISR;
dummy=dummy; //Suppress compiler warning
//* Read the output state
if ( (AT91F_PIO_GetInput(AT91C_BASE_PIOA) & INPUT_SERVO2_CAP) == INPUT_SERVO2_CAP); //Don't do anything, rising edge
else //Falling edge -> capture value in
{
measure.duty_channel_2 = TimerBaseCPWM->TC_CV;
}

cContextSwitchRequired = pdFALSE;

portEND_SWITCHING_ISR( ( cContextSwitchRequired ) );

/* End the interrupt in the AIC. */
AT91C_BASE_AIC->AIC_EOICR = 0;
}

The interrupt is configured according to following lines:

AT91F_PIO_CfgInput(AT91C_BASE_PIOA, INPUT_SERVO2_CAP);
AT91F_AIC_ConfigureIt (AT91C_BASE_AIC, AT91C_ID_PIOA, PIO_INTERRUPT_LEVEL, AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE, ( void (*)( void ) ) pio_ISREntry);
AT91F_PIO_InterruptEnable(AT91C_BASE_PIOA, INPUT_SERVO2_CAP);
//* set the interrupt by software
AT91F_AIC_EnableIt (AT91C_BASE_AIC, AT91C_ID_PIOA);

My wrapping file looks like this:

RSEG ICODE:CODE
CODE32

EXTERN pio_ISR
PUBLIC pio_ISREntry

; Wrapper for the USB interrupt service routine. This can cause a
; context switch so requires an assembly wrapper.

; Defines the portSAVE_CONTEXT and portRESTORE_CONTEXT macros.
#include "ISR_Support.h"

pio_ISREntry:

portSAVE_CONTEXT; Save the context of the current task.

blpio_ISR; Call the ISR routine.

portRESTORE_CONTEXT; Restore the context of the current task -
; which may be different to the task that
; was interrupted.

END

Thanks in advance!
//MB


RE: Using ISR-wrapping with PIO

Posted by Richard on May 11, 2005
I replied to your other post.

Regards.


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




Copyright (C) 2004-2010 Richard Barry. Copyright (C) 2010-2016 Real Time Engineers Ltd.
Any and all data, files, source code, html content and documentation included in the FreeRTOSTM distribution or available on this site are the exclusive property of Real Time Engineers Ltd.. See the files license.txt (included in the distribution) and this copyright notice for more information. FreeRTOSTM and FreeRTOS.orgTM are trade marks of Real Time Engineers Ltd.

Latest News:

FreeRTOS V9.0.0 is now available for download.


Free TCP/IP and file system demos for the RTOS


Sponsored Links

⇓ Now With No Code Size Limit! ⇓
⇑ Free Download Without Registering ⇑


FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

Renesas Electronics Gold Alliance RTOS Partner.jpg

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

Atmel RTOS partner supporting ARM Cortex-M3 and AVR32 microcontrollers

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

Xilinx Microblaze and Zynq partner

Silicon Labs low power RTOS partner

Altera RTOS partner for Nios II and Cortex-A9 SoC

Freescale Alliance RTOS Member supporting ARM and ColdFire microcontrollers

Infineon ARM Cortex-M microcontrollers

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

Cypress RTOS partner supporting ARM Cortex-M3

Fujitsu RTOS partner supporting ARM Cortex-M3 and FM3

Microsemi (previously Actel) RTOS partner supporting ARM Cortex-M3

Atollic Partner

IAR Partner

Keil ARM Partner

Embedded Artists