Quality RTOS & Embedded Software

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


Loading

Delayed FreeRTOS failure

Posted by Tamir Michael on August 24, 2012
Hello,

I have a LPC2478 running 14 FreeRTOS tasks without issues.
However, once I add one task (the 15th) the scheduler starts up, and them, during context switch the second context switch, the most innocent looking instruction (NOP...) will branch the processor to some address. If I disable a background interrupt (1000 Hz) that has a higher priority than the kernel and runs while the scheduler starts up the system will start up normally. If I enable that interrupt source but empty the ISR the systems starts up correctly. If I insert a slight delay (30 NOPs) into the ISR - the system will fail with 15 tasks! I don't see how an empty ISR can corrupt the kernel, unless there is some kind of timing issue at hand.
I have enough heap and stack, and I'm out of ideas...
Any comments are welcome!

Thanks in advance.

RE: Delayed FreeRTOS failure

Posted by Richard on August 24, 2012
The ARM7 port does not support interrupt nesting, so I'm not sure the priority of the interrupt is that relevant - presuming you have not changed the FreeRTOS code.

Is your high priority interrupt using the FIQ, or IRQ?

Regards.


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


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

Latest News

NXP tweet showing LPC5500 (ARMv8-M Cortex-M33) running FreeRTOS.

Meet Richard Barry and learn about running FreeRTOS on RISC-V at FOSDEM 2019

Version 10.1.1 of the FreeRTOS kernel is available for immediate download. MIT licensed.

View a recording of the "OTA Update Security and Reliability" webinar, presented by TI and AWS.


Careers

FreeRTOS and other embedded software careers at AWS.



FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

Espressif ESP32

IAR Partner

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

Renesas

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

Xilinx Microblaze and Zynq partner