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


AVR32: portEnterCritical vs DisableInterrupts

Posted by Jeff Henshaw on June 19, 2009
vportEnterCritical() disables all interrupts and then increments ulCriticalNesting.

My question is when should I use one versus the other? I'm not sure what ulCriticalNesting is for, there's a number of things in the AVR32 port that don't match the documentation. Probably because the AVR32 is kinda weird. :-)

Also, any issues using vportEnterCritical() before the scheduler is running?

Thanks !

RE: AVR32: portEnterCritical vs DisableInterr

Posted by Richard on June 19, 2009
The only method of disabling and enabling interrupts that should be used are calls to taskENTER_CRITICAL() and taskEXIT_CRITICAL() as these maintain a nesting count. You should not manipulate ulCriticalNesting directly, it is purely for use of the kernel.

It is fine to use the macros before the scheduler has started, but interrupts will remain disabled until the scheduler has been started.

Also note that some ports don't disable all interrupts, but only those up to the priority used by the kernel.


[ 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