If you can see the appendix you see that the matter concerns the stepping engine controlled with the system based on the programmable logic circuit and IC. Control system performs the digital control to provide the given overfall. This circuit consits of multiplexers, ADDER, D-trigger blocks and etc. The given number of steps (impulse) is given to inputs of multi-channel block of key elements. The maximum quantity of steps is brought by signal to Adder's input.