so I replaced my 74hc14 chip on my Hobbycnc AND..... 4th axis is still dead. So that means ether I have a broken connection TRACE/SOLDER POINT, BURNT yes BURNT trace. :tired: or the motor controller chips input pin(s) may be burnt out. I have proven that my ucncv4 board's 4th axis output is working just fine. Long story short I miss plugged my PSU into the UCNCV4 backward once plugging 24v into grd. the only damage that seems to have happend happend to my hobbycnc controller of all things. I discovered it when a fuse (REALLY A PCB TRACE) on the backside of the hobbycnc board started billowing a lot of smoke. this happend a few years ago. But I've never messed with the 4th axis till just now. worst case rather then pull everything apart I may just add a single motor controller to drive the rotary 4th axis. far less painful then trying to un-fux my fux up or so I claim.