Quality RTOS & Embedded Software

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


when a task is switched out, what will happen to its IOs?

Posted by sdfewa on January 21, 2018

If task A reads/writes from/to IOs and the scheduler switchs it to a higher priority task B which doesn't touch any IOs task used. Do they keep their state in general? There is no any kind of reset action during the context saving/switching, right? I assume task A doesn't have critical sections or has finished its critial sections.

And further, task B can do anything she wants to the IOs until task B is out?

when a task is switched out, what will happen to its IOs?

Posted by richard_damon on January 21, 2018

FreeRTOS itself will know nothing about the I/Os and tasks can do what every they want to them. Unless you write code in the trace macros, or modify the files in some way, I/O ports will have no idea of what task is runing, so a task switch won't affect the I/Os.

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

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

Latest News

Meet us at Embedded World. Hall 3A-525.

Hear from Richard Barry at Embedded World. Feb 28, 16:00, Hall 4-428.

Video: Watch James Gosling & Richard Barry at re:Invent, Las Vegas 2017.

FreeRTOS kernel V10.0.1 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