X Axis step direction does not change

[ascended 0]

As a follow on from here: http://umforum.ultimaker.com/index.php?/topic/2915-z-limit-switches-not-doing-anything-after-157-pcb-upgrade/ in order to have a relevant title.

I'm having issues that the X axis always moves the same direction. This happens on a brand new ultimaker PCB (1.5.7) with 3 different arduino megas (one of which has a blown pin - as in totally missing - on the Z top limit input.)

X Axis traces, top trace is step, bottom trace is direction (pegged to 5v)

Y Axis traces, top trace is step, bottom trace is direction (note the step)

Both are two 1mm moves in one direction, two 1mm moves in the other.

 

[gr5 2,172]

Nice job debugging!

Can you send the board back? Is it under warranty? If it is new you can do a support ticket and they should send you a new board out right away as this is a clear problem.

Also did you load the Marlin firmware that comes with Cura into your Arduino? There are many configurations for which pin of the Arduino controls which stepper pins and so on.

I would also cut power and remove the arduino and check the signal path from the arduino connector to the stepper driver.

Did you check this signal on the stepper driver or the arduino? It might be a bad connection between the arduino and the ultimaker PCB. And the stepper driver may be gently pulling that signal to 5V.

 

[ascended 0]

I've confirmed that all the tracks are intact, the pin on the stepper has continuity to the MCU pin.

There are no shorts to ground or 5v, or any other pins.

 

[ascended 0]

Ah, you posted as I was tracing things out

I've run the first run wizard in Cura on each of the arduinos to load the firmware onto it.

Both traces are done with the same stepper driver, without disconnecting the logic analyser pins, just moving the driver from point to point.

As previously posted, I've traced the pins and checked for shorts on both boards separately and together, and ensured the pin on the driver gets a connection as well.

 

Nice job debugging!

Can you send the board back? Is it under warranty? If it is new you can do a support ticket and they should send you a new board out right away as this is a clear problem.

Also did you load the Marlin firmware that comes with Cura into your Arduino? There are many configurations for which pin of the Arduino controls which stepper pins and so on.

I would also cut power and remove the arduino and check the signal path from the arduino connector to the stepper driver.

Did you check this signal on the stepper driver or the arduino? It might be a bad connection between the arduino and the ultimaker PCB. And the stepper driver may be gently pulling that signal to 5V.

 

[gr5 2,172]

It sounds like the PCB is fine. So probably the Arduino is bad. Did you say you tried 2 different Arduinos and they both had the same problem? Or was there only one Arduino? Or did the first Arduino have a different problem?

I think you should buy another Arduino board and also just to be safe, I would remove the X stepper driver. I would test the voltage on the DIR pin on the X stepper and only if it works, *then* put the X stepper driver back in - there is a small (very small!) chance that the stepper driver damaged the Arduino. This is pretty unlikely as the Arduino is designed to not get damaged easily.

 

[ascended 0]

I actually tried 3 arduinos. I ended up finding a 4th one lying around that had not been touched by the old ultimaker board, and it worked.

 

[gr5 2,172]

oh! So that probably means the old ultimaker board was breaking that pin - actually probably the X servo driver was destroying that arduino pin! You could possibly reroute using another signal. You would have to make your own custom drivers that use a different arduino pin.