pulse
When the input goes from inactive to active, the output will turn on for a brief period of time. The default is 100ms. An optional parameter for the duration of the pulse, in milliseconds, may be placed in the cell after the word, like "pulse 1500". An optional second parameter controls the number of pulses delivered. The default number of pulses is 1. "pulse 50 2" could be used to "double tap" a trigger.
If I understand what you want, that should do it.