Hi Josaami,
No worries about your English.

Yes, each pulse on the Digital Trigger (LPT Output) is an impact.
The frequency of these pulses (set by feed rate) is related to the transducer you are using. For example ; the maximum I have achieved with an electromagnet is 21Hz
http://hobbymaro.puhasoft.hu/Tweakie/Impact1.wmv and an air operated solenoid around 5Hz.
Something else you may wish to consider, which can produce similar results but in an entirely different way is DotG.
http://dotg.weebly.com/This software is free to download and use - it produces Mach3 compatible GCode and English translations of the manuals are available from their website. (Perhaps Google Translate may be useful in your deciphering of these documents).
Tweakie.