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


Timing methods

Posted by Nobody/Anonymous on August 18, 2005
I would like to be able to set a pin high for a certain amount of time and then set it low at the end of the specified time.

I am using an ATmega128 chip and I would like to be able to obtain this pulsing of the bit without doing inline assembly code. I didn't see a specific timer function in the RTOS and my only thought as far as being able to do some timing with the RTOS was to set the bit and then delay the task that turned the bit off for a certain amount of ticks. This would provide some measure of timing, but not the most accurate, and it does not seem the best way. If anybody has any suggestions, please let me know.


RE: Timing methods

Posted by Nobody/Anonymous on August 19, 2005
What sort of frequency do you require? You can just set one of the timer output peripherals on the chip to do this with no software overhead. If low frequency then you could also use a timer interrupt (just like the RTOS tick).

RE: Timing methods

Posted by Nobody/Anonymous on August 19, 2005
The internal clock on the chip runs at 14.7456 MHz. I want to be able to do timing in milliseconds.

Yah, I had it pointed out to me that I should just check into the timers on the chip. I will do that.

Thanks for the help,

[ 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