Clear TimerA From Hardware Pin

I am working on my first MSP430F5510 design (64 pin).

I understand how to generate PWM signals using TimerA in Up/Down counter mode. Is it possible to clear the timer using a signal on an MSP 430 pin instead of using an interrupt service routine? In other words, I would like to clear the timer when an MSP430 pin goes high and start counting again when the pin is low. Do I need to use a particular pin to reset the timer?

Thank you for your response.

Max