Quality RTOS & Embedded Software

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


SAM7 and GDB

Posted by Nobody/Anonymous on November 7, 2006
I'm using the great FreeRTOS on an at91sam7s(arm7tdmi) in conjunction with a
spi color lcd (nokia's) and a mmc card, and I get random DataAbort which I
need to debug.

I'm using gcc and openocd+gdb and I'd like gdb to know about the USER stack
when the program is beeing stopped debugged in ABORT mode.

More generally, it would be interesting to switch from stack to stack using
the gdb "thread" command.

RE: SAM7 and GDB

Posted by Richard on November 7, 2006
I am not proficient enough in GDB to answer your questions directly, but looking at the user stack is quite straight forward in raw memory format.

Inspect the variable pxCurrentTCB. This will tell you where the last stored top of stack was and where the bottom of the stack is. You can then simply inspect this memory in the memory window. You can see the high water mark of the stack as the stack is filled with 0xa5 prior to the task commencing.

Most data aborts originate from stack overflow. Try increasing the stack allocated to your tasks.


RE: SAM7 and GDB

Posted by david on November 8, 2006

Yes in the meantime I investigated more, and it happenned to be really a stack size problem.

Do you think it's worth adding optional (for debugging) automatic check code for the stack use in
vApplicationTickHook() or in a better place ?

I'll investigate the use of gdb, so to try and make it aware of "threads" using pxCurrentTCB.

Thanks a lot,

Best regards,


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

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

Latest News

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

Version 10.1.1 of the FreeRTOS kernel is available for immediate download. MIT licensed.

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

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