Is there a way to manually turn Pins on/off?

I'm trying to control an RC car and i#ve run into a road block so to say. The cars speed controller needs an activation signal before accepting any PWM signal. That activation signal isn't PWM, but a specific pattern.
So my question is, is there any way to turn a Channel on and off manually, so i can put together the activation signal i need?

Start by reading the PCA9685 driver API and its channel-output controls. Determine whether a channel can be manually enabled or disabled independently of PWM, then verify that the behavior can produce the activation pattern requested for the RC car; done means the supported control is documented and usable.

Written by the indexing model from the issue text.