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

Block task until an event happens (xTaskNotify didn't fit)

Posted by gutolaureano on November 16, 2015

Hello,

I would like some help to find out how use the FreeRTOS resources:

I need lock a task execution until an event (interrupt) happen, but i need unlock the task only if this event happened after the task has been locked, interrupts that happened before the lock does not care, the first feature that came in mind was the task Notify events, but I figured out that if any event happened before the xTaskNotifyWait it will not lock (because the state will be eNotified) even if I set all bits in ulBitsToClearOnEntry ( is there a way to clean the eNotified state before calling xTaskNotifyWait() ?)

Stopping the interrupt until the locking moment is not an option, any suggestions? (I am new to the RTOS world, still learning how to model my solutions using RTOS, sorry if this is a trivial problem)

Thanks for your time! Gustavo


Block task until an event happens (xTaskNotify didn't fit)

Posted by davedoors on November 16, 2015

You can call xTaskNotifyWait() with a block time of 0 to clear the notification state before you call it again to wait for the interrupt. In 8.2.3 there is also a function xTaskNotifyStateClear().


Block task until an event happens (xTaskNotify didn't fit)

Posted by gutolaureano on November 16, 2015

Thank you! Exactly what I needed!

I'm using 8.2.1 atm, I can just update my Freertos source to the latest? no need any adittional changes, right?

Thanks again


Block task until an event happens (xTaskNotify didn't fit)

Posted by rtel on November 16, 2015

Yes - it should be just a drop in replacement.

Regards.


Block task until an event happens (xTaskNotify didn't fit)

Posted by gutolaureano on November 17, 2015

Perfect! Thanks


[ 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