Z drive heads down

[matter68]

My Rostock Max V2 was working fine, but struder was acting funny so I was troubleshooting. There was a spark from the front of the board and since then the Z drive is all wonky. When I click on the home button the x and y move properly the Z tries to crash to the bottom. I even went in and tried to reverse the drive in the config file, still nothing. If I give the G28 command everything moves up properly until the Z hits the limit switch at which point it begins its high speed decent. No idea where to start on this one, any suggestions would be greatly appreciated.

[Earthbound]

Try reloading firmware. If still wonky, try erasing the EEPROM and then reloading the firmware again. If the spark did not damage the circuitry, it may still have corrupted flash or EEPROM.

[Polygonhell]

If there was a spark from the board, the odds are something shorted, your going to want to start by checking all of the wiring. But you could well have damaged the board.
If you connect the Y stepper to the Z driver, does it behave the same way?

[matter68]

Cleared the eeprom and reloaded the firmware, still wonky. Switched out the Z and Y plugs on the board and the Y took the dive instead of the Z, so its something coming from the board I imagine. Its never the inexpensive piece the gets smoked..lol

[Earthbound]

The RAMBo has 5 stepper drivers (for X/Y/Z and dual extruders). You could get into the firmware files and re-task the spare driver (E1) to handle Z axis duties.

[matter68]

I appreciate the information, how do you re-task the E1? I went under pins-h but really had no clue and didn't want to make things worse. If I can do it that way vs getting a new board, that would be fantastic!

[Eaglezsoar]

I appreciate the information, how do you re-task the E1? I went under pins-h but really had no clue and didn't want to make things worse. If I can do it that way vs getting a new board, that would be fantastic!

Ultimachine.com also repairs boards instead of having to buy new. Hopefully someone with the experience of working with the pins.h file will help you.

[Earthbound]

Start by locating the pin.h file and make a backup copy pinsOld.h before we create any new chaos. Then open Repetier.ino in the Arduino IDE.

To reassign steppers for RAMBo, scroll down to line 1448 in pins.h, where you'll see * RAMBo Pin Assignments.

We're concerned with the lines just below that (1471-1477 and 1497-1501)

#define Z_STEP_PIN 35 -- change the 35 to 33
#define Z_DIR_PIN 47 -- change the 47 to 42
#define Z_MIN_PIN 10 -- leave alone
#define Z_MAX_PIN 30 -- leave alone
#define Z_ENABLE_PIN 27 -- change the 27 to 25
#define Z_MS1_PIN 68 -- change the 68 to 63
#define Z_MS2_PIN 67 -- change the 67 to 64

<skipping some lines>

#define E1_STEP_PIN 33 -- change to 33 to 35
#define E1_DIR_PIN 42 -- change the 42 to 47
#define E1_ENABLE_PIN 25 -- change the 25 to 27
#define E1_MS1_PIN 63 -- change the 63 to 68
#define E1_MS2_PIN 64 -- change the 64 to 67


With POWER OFF, plug the Z stepper lead into the E1 (rightmost) output header. Power up Max and upload the revised firmware. Then go back to the manual and follow the steps for checking stepper/axis direction.

[Eaglezsoar]

Earthbound, thank you for helping out with the reassignment of the pins.
Everyone learns when things this technical gets posted.
Great Job!

[matter68]

First off, Thank you Earthbound for the directions. Unfortunately in the new configuration I get no response from the Z tower at all. I still have hope

[Earthbound]

My fault for not stating that this would work - in theory - , but that I had not actually tried it. All of the changes to pins.h are correct. I dug around and realize that there is one thing I overlooked. All of the pin assignments are related to how the microcontroller is connected to the stepper drivers. There is an additional chip that regulates the stepper current. By default it has the 5th stepper driver shut off (set to zero output current).

In the Arduino IDE, go to Configuration.h and scroll down to line 701 which probably reads:

#define MOTOR_CURRENT {175,175,175,200,0}

Your file could have different values, if you were instructed to change them due to having a kit with Kysan motors (pg 216 in the manual).

The last value will be 0, inhibiting the 5th stepper driver.

Swap the 3rd and 5th values. So if your numbers matched the ones above you'll end up with {175,175,0,200,175}.

Upload and see if that does the trick... because I am guessing that the MOTOR_CURRENT values are parsed as X,Y,Z,E0,E1 but I have no evidence of it, only a logical guess. Also, sidebar, E1 that we are re-assigning has nothing to do with Extruder 1. Extruder 1 uses the E0 stepper drive.

[koontzrd]

Thanks for putting this out there! Had to change my X over to E1. In my case it was x, and it would only go down. Used M119 to confirm that end switches were ok. Then confirmed that it was a RAMBO issue by following the process on a different post (http://forum.seemecnc.com/viewtopic.php?t=5534) and tested the output of x on the z tower and then tested the output of z on the x tower. (dont forget to turn off before moving plugs, and also dont forget to keep stop switches aligned with the motor - ie when i put the x plug in the z tower, I also put the x end stop in the z tower)

The line numbers have changed in the files since this thread was originally posted, but the process still worked perfectly! I used ctl-f search to find RAMBo Pin and then went from there - and back in business.