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

Using FreeRTOS from Scratch.

Posted by erik on May 24, 2007
Hi,

I've been trying to use the FreeRTOS from scratch. I'm using IAR EWARM for the ARM LPC2129. I've gotten the demo to work and I have read through the API thoroughly. I believe I've included the bulk of the files necessary to compile, since I can compile. The issue that I come to is when I'm trying to create a task it seems to freeze the entire system and an interrupt goes off. The following is what I'm doing.


StarttestMath();
vTaskStartScheduler();


void StarttestMath(void)
{
xTaskHandle TestHandle;
xTaskCreate(TestMath , "Test", 4, 0, 3, &TestHandle);
}

I am not using the originaly Cstartup.79

Can someone help me?
Thanks,
Erik


RE: Using FreeRTOS from Scratch.

Posted by embeddedc on May 25, 2007
Is it a peripheral interrupt or an abort that is causing the problem?

If it is a peripheral interrupt then make sure you don't allow any interrupts to execute that use the FreeRTOS API prior to the scheduler being started.

The most likely cause is something in the startup file. The startup file must:

i/ Call main() in Supervisor mode (or at least you must switch to supervisor mode prior to starting the scheduler).
ii/ Setup stacks for Supervisor and IRQ mode. FIQ mode too if FIQs are being used. You need not setup stacks for user mode as the kernel does this for you.
iii/ Setup the VIC to vector directly to interrupts with not code in between.

The best thing to do is not start from scratch but modify one of the demos provided for you.


[ 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