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

How does FreeRTOS handle the spurious int?

Posted by francis wang on August 20, 2009
Spurious interrupts are possible to occur in the ARM7TDMI based microcontroller such as the LPC2114/2124/2212/2214 due to the asynchronous interrupt handling.
So does FreeRTOS use certain method to deal with this kind of interrupts?

Besides, if I use soft I2c in a task, should I use mutex lock-unlock to invoke the i2c routine or use the enter critical - exit crital method? what is the diffence?If I use the mutex method , the i2c routine is still possibly interrupted by the hardware interrupts,isn't it?


Kindly regards!
wFrancis

RE: How does FreeRTOS handle the spurious int

Posted by Dave on August 20, 2009
Users should ensure that spurious interrupts are handled correctly in accordance with the documentation from the device manufacturer. For example, NXP have an ap note describing how to handle them. I think some FreeRTOS demos have handlers for these interrupts, but probably not all. Generally you just clear the interrupt then return.

You may be better posting your unrelated questions in two separate threads, that way more people will see the second question.

I would first say if you are using I2C in just one task then do you need a mutex or critical section at all? Normally they would only be used to prevent more than one task accessing the same peripheral at the same time.

RE: How does FreeRTOS handle the spurious int?

Posted by John W. on August 27, 2009
I usually develop what I call 'interrupt_grabber' that handles all undefined and/or unhandled IRQ's in a system - and just do a while(1); in them so I can identify what's going on in the system - just a little different way to answer your question.


[ 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