Hello everyone, I would like to use an external pulse source to use as the clock source for timer3 on my Mega2560. I can see in the data sheet that it says to use pin Tn where n is the timer number "3", but I am having some trouble figuring out what physical pin this is on the Arduino Mega2560. If anyone could point me in the write direction, I would be much obliged.
Thanks!
Datasheet, page 2.
Looks like pin 8 on the chip.
It also looks like that pin is not brought out to an external pin on the board (if you are using the Mega 2560 Arduino board). (See the reference schematic).
Thank you Nick!
I had found the pin and port address (PE6) on the datasheet, but I couldn't find it in the pin mapping spreadsheet I found:
https://spreadsheets.google.com/pub?key=rtHw_R6eVL140KS9_G8GPkA&gid=0
After you answered I scrolled down on the speadsheet and low and behold (I´m a bonehead) its right there as "Functions not available..."
That kind of puts a damper in my designs, oh well
Now just out of curiosity, do you think there is a reason why they didn't bring those pins out to headers other than cost and/or "who could possibly use that?"
Thanks!
Am I wrong or is the external clock source for timer 5 (T5), the only one of the extra 3 timers that is brought to out to a header pin on the mega2560?
In case anyone else finds this useful:
For the Arduino Mega2560
Timer0 external clock source: PD7 (Pin 38)
Timer1 external clock source: PD6 (Not brought out to a pin.)
Timer2 external clock source: ? I can't seem to find it on page 2 of the datasheet, or anywhere else for that matter. Anyone?
Timer3 external clock source: PE6 (Not brought out to a pin.)
Timer4 external clock source: PH7 (Not brought out to a pin.)
Timer5 external clocksrouce: PL2 (Pin 47)
According to the datasheet, the external clock input is good to about a 6.4 MHz (assuming your system clock is running at 16 MHz).