Quality RTOS & Embedded Software

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




Loading

SAM7X Demo and PIT Spurious Interrupt Issue

Posted by Çağlar Akyüz on January 31, 2007
I am using SAM7X Web demo with GCC. In addition to the default Demo settings, I added an SPI interrupt and vApplicationTickHook function. My problem is that vApplicationTickHook function is called (sometimes) accidentally(i.e. spurious interrupt). It should be called within each 1 msec. It is called generally but sometimes period changes to ~ 40 microsec and then 1 msec again. Following is the what I see on my scope.(I'm toggling a pin in vApplicationTickHook)


--------- ---------- ---------
| | | | |
| | | | |
| | | | |
---------- ---- ---------
1msec 1mes 1mes 40u 1msec 1mesc ..................


I relized that if I send less data from Ethernet, occurence of these abnormal pulses decreases,also. I wonder if anybody has faced this kind of behaviour.

Best regards,
Caglar Akyuz


RE: SAM7X Demo and PIT Spurious Interrupt Iss

Posted by Çağlar Akyüz on January 31, 2007
I'm sorry for the last message because that scope output was not what I intended to draw. Let me clarify :


1 msec High, 1msec Low, 1msec High, 40 microsecond low, 1msec High...and goes like that.

Sorry for the inconvenience.

Caglar Akyuz

RE: SAM7X Demo and PIT Spurious Interrupt Iss

Posted by embeddedc on January 31, 2007
Have you included a spurious interrupt handler?

AT91C_BASE_AIC->AIC_SPU = (int) AT91F_Spurious_handler;


[ 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