Quality RTOS & Embedded Software

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


FreeRTOS with boot loader

Posted by Nobody/Anonymous on September 19, 2006
I want to start my initialisation with a bootloader, witch gave me the opportunity for updating the RTOS.

Also should it be possible to jump from the RTOS back to the bootloader to update the OS.

The first point should be no problem.
But I have no idea, how it is to update while running.

Could it work like this:

- stop all running tasks
- jump to bootloader
- overwrite the RTOS
- (software reset) restart the system

Is it enough to stop all running tasks or must there be done more?

Is this the way it will work?

Have you some experiences with updating a FreeRTOS?
Are there some examples?

Thanks for Your Answer,

RE: FreeRTOS with boot loader

Posted by Richard on September 19, 2006
The x86 ports implement the end scheduler function as these ports are booted from DOS - and therefore can return to DOS when the scheduler ends. Generally with other ports I have not bothered to implement the end scheduler function as there is nowhere for the execution to return to. You could have a look at the x86 ports to see what these do, but I think this would be overkill for your needs - really all you want to do is stop the scheduler running then reset the system. Resetting the processor will ensure the scheduler starts up in a consistent initialised state, so you don't need to do this manually.

To stop the scheduler you need to stop the tick interrupt. This can be done by halting the timer used to generate the tick. Alternatively you can disable interrupts (but this might effect your ability to reprogram the flash) or call vTaskSuspendAll() without calling vTaskResumeAll(). This last option would not stop the tick interrupt, but it would prevent the tick interrupt from attempting to switch task contexts.


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

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

Latest News

FreeRTOS v10.2.0 is available for immediate download. MIT licensed, and including RISC-V and ARMv8-M (Cortex-M33) demos.

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

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


FreeRTOS and other embedded software careers at AWS.

FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

Cadence Tensilica Cortes

Espressif ESP32

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

Xilinx Microblaze and Zynq partner