I am having a very strange issue. I am using a similar layout as the RepRap Stepper Motor Driver 1.2 except that I am wiring it together on perfboard myself. So three driver boards in all attached to three stepper motors. When everything is connected except the X stepper motor, the machine works fine. The Y and Z axis move smoothly. If I then connect the X stepper to its driver board (when everything is off) and then turn on the machine, the X axis works but the Y and Z stop functioning. The Y and Z hiss and stutter and sometimes they even start moving uncontrollably in one direction. The Y and Z motors also get hot. They act as if they are being short circuited in terms of heat output. My circuit deviates from version 1.2 in that all three drivers share a single V-ref pot. Also, they all share a single oscillator. I tried wiring the oscillator to one of the L297's and then connecting their sync lines, but the issue stayed the same. Can anyone think of what might be causing this? I don't see how adding the load on the x-driver board can cause the other two to stop working correctly.
To show you visually what is happening:
(Y and Z function correctly)
(Only X functions correctly)
Also, if the X stepper motor is attached, but I disable the X-driver using the L297 disable pin, then Y and Z works fine. I thought it might be a problem with my power supply. So I upgraded my power supply to one that had 3 times the calculated amperage, but the issue stayed the same. I know the motors are wired correctly because they all individually work. I only run into a problem when all of them are wired at once.
Update: I tried replacing the L297 on the X driver but the problem remains. With X disabled, Y and Z function without hissing. With X enabled, strong hissing is heard and only X moves smoothly. I think my next step will be to try to replace the L298n on the X driver.
Do you guys normally hear a hissing? I know the chopper is supposed to make a noise but when only Y and Z are enabled, I hear no hissing and they work perfectly.
Update 2: Solved!!!
The problem had nothing to do with the X axis. I had combined all three stepper drives onto a single 3" by 4" board, and in doing so, I forgot to multiply the capacitor on the +5V line. When one of the steppers would stop at half a step, it would put a heavy load on the 5V side and the other chips would become unreliable (jitter, move, act crazy). I guess when I only had two motors enabled, the cap on the board could handle the load. I put a huge capacitor on the board and everything is running smoothly now. This is funny because I had assumed this was a problem with the 24V line. I already had a 4000uF cap on there and changed my power supply to a 24A one. I hope this helps someone else that runs into the same problem.
Update 3: Solved Secondary Problem with Acrs