I built a cnc router. The Control console uses (3) KL-4030 Drivers to drive (3) KL23H286-20-8B motors, a CNC4PC C10 Parallel Port Interface card and using Mach3 software. I built a 555 square wave generator to test out the wiring. I insert the square wave (800Hz @ 5v p-p) onto pin 2; 4; and 6 and all motors run fine in both directions. My problem is getting Mach3 to do the same. I watched the configuration video, followed all instructions, and all seems to be in order. When I go to Motor Tuning, I choose axis, insert proper step value ( even improper step value) play with Accel & Velocity, save axis settings then press up or down keyboard key. Sometimes I get motion sometimes I don't. I can't get continuous running. Same on all axis'. Tried using Mach3 from 2 different computers to no avail. Scope shows input to x-step (pin 2) about 6us pulse 5vp-p (555 is much longer pulse). I know it must be a setup fluke but I can't find it. I took some pics of my setup. I'll try to post them if I can. If not, you can PM me, I'll be happy to forward you a copy. It could help to clarify things. Any and all help would be appreciated. Thanks gentlemen.