1.If jumper is hit the position of ON DP, that means 16 segment (4988) or 32 segment (8825)Jm connected motor 2.Jv connect 5v and 12v-24v power supply 3.Jc E, S, D, G, respectively corresponding to the connection of the Enable/Step/Dir/Gnd drive signal output Notice: Pay attention to when installation direction, otherwise it may burn drive even the mainboard