Quality RTOS & Embedded Software

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




Loading

Task switch

Posted by Nobody/Anonymous on May 4, 2006
Hi,

i use the RTOS 3.2.2 with an Atmel SAM7.
In code there are 3 tasks with the same priority and they can use the same hardware (for example SPI Interface ).
If a task want's to use the hardware it checks a flag and use the the hardware (with setting and clearing of the flag) or it waits until the flag is cleared.
This works fine without any problems. Depending on the hardware the waiting time can be very short and i don't want to use vTaskDelay(1).

Is it better to use vTaskSwitchContext() instead or is it not recommended.

Thanks for the help.

Regards

Rainer

RE: Task switch

Posted by Nobody/Anonymous on May 4, 2006
I think maybe you should use a semaphore instead of a flag to avoid race conditions.

Never call vTaskSwitchContext()!!!!!! Use taskYIELD() instead.

You could raise the priority of the task that has the semaphore, then lower it again before it gives it back. This would prevent the other tasks from having to poll the flag.


[ 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