Counting the amount of pulses

Hello,

I'm using a GUI to monitor a system. In this system there is an encoder that generates pulses if an engine (crankshaft) is turning. Now I need something that counts the amount of pulses that have been generated until another pulse (from another device) is given. So to be clear, there are two different channels of pulses.

Has anyone an idea of how I can do this?

With Regards Hans Vertongen