Timing methods

Kernel
1

nobody wrote on Thursday, 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.

Thanks

2

nobody wrote on Friday, 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).

3

nobody wrote on Friday, 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,
Josh