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


Getting kicked out of the tast

Posted by mishung on February 15, 2017

I am getting a strange behaviour out of my FreeRTOS on Xmega32D4 (AVR-GCC). Whenever there is a while loop without any vTaskDelay() and it takes a couple miliseconds to complete (for example receiving data from usart which could take as much as 30ms) I seem to get kicked out of the function earlier. For example I am supposed to receive 30B from the buffer but I only get 28B. If I add vTaskDelay(1) into the loop, everything goes fine. Same goes for a lot of other examples and not just an USART data recovery. As far as I know I am not using any watchdog timer.

What could be the cause of this?

Getting kicked out of the tast

Posted by rtel on February 15, 2017

It sounds like a logic error, or a timing error in the interaction with the hardware. Without seeing how you are determining that the loop should exit after 28 bytes, when you actually want 30 bytes, it will be impossible to even guess what might be the cause. Post the code that is determining that the loop should be exited, but even after seeing the code it might be that we can't answer the question without also studying the hardware manual (which we are not going to do).

[ 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