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


Excessive Memory Usage with PIC32 port

Posted by Grant Brown on October 23, 2008

Port : PIC32

I have stripped all of the custom tasks etc out of the PIC32 demo and removed the source files etc for the above tasks.

This has resulted in a program with only 3 custom tasks (I wrote them and 1 is copied below for reference) which simply flash LED's. All there tasks are contained in the main file (main.c)

But when I compile the program and then check the memory usage I end up with the following memory usage as reported by the MPLabs Memory Usage Gauge,

Program Memory : 18600 Bytes (out of 536560)
Data Memory : 31404 Bytes (out of 32768)

This really seems excessive given that whats left is basically an empty project with the RTOS just ticking over.

Am I missing something or is it normal for 95% of the data memory to be used up like this.

The project files are,

Source files,


Header Files

C:\Program Files\Microchip\FreeRTOS\Demo\PIC32MX_MPLAB\FreeRTOSConfig.h

Here is a typical custom task

static void Grants_Task( void *pvParameters )
portTickType xLastExecutionTime;
xLastExecutionTime = xTaskGetTickCount();
for( ;; )
vTaskDelayUntil( &xLastExecutionTime, 1000 );
PORTToggleBits(IOPORT_D, BIT_0);

Kind Regards
Grant Brown

RE: Excessive Memory Usage with PIC32 port

Posted by Dave on October 23, 2008
This really should be an FAQ. All you are seeing is the heap RAM which will mostly be free RAM and can be set using the configTOTAL_HEAP_SIZE setting in FreeRTOSConfig.h. http://www.freertos.org/a00111.html

[ 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