Steppers acting weird

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Farr0wn3d
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Steppers acting weird

Post by Farr0wn3d » Wed Mar 21, 2018 3:06 am

I made some changes to my carriage a day or 2 ago, and with that I took the loom off the cable that goes to the extruder assembly so that I could adjust wire lengths to make everything fit cleanly. I had changed my heater cartridge, so when I turned the printer on, I did a PID autotune, and since I swapped my regular titan for a mirrored titan I changed my extruder's steps/mm to a negative value through the communication window, to see if that would mean I didnt have to reflash the firmware entirely. When I went to purge my filament, I noticed that my extruder was just making a very quick, higher pitched buzz for a split second, and then nothing, even though I was sending the command for 100mm, which normally takes 10 seconds to complete. I tried all my other steppers and theyre all acting the same way. I tried reflashing the firmware with the OEM file, to no avail. Rebooted my computers, reset the rambo, closed and reopened s3d, ALL NOTHING.

Does anyone have any ideas? the blade fuse, and the on-board removable fuse are both good.

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insta
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Re: Steppers acting weird

Post by insta » Wed Mar 21, 2018 4:09 pm

You don't use negative steps per millimeter ...
Custom 3D printing for you or your business -- quote [at] pingring.org

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Farr0wn3d
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Re: Steppers acting weird

Post by Farr0wn3d » Thu Mar 22, 2018 12:56 am

Fair enough. I saw that mentioned on a marlin forum, so I gave it a shot thinking that I could just reverse it if it gave me grief. But seeing as how I've reflashed the firmware and the problem persists, I assume that unless that negative value caused some sort of physical damage to all of my stepper drivers simultaneously, there must be something else at play here. If I would have been thinking clearly, I would have just swapped the pins on the extruder motor wiring at the board like I did for the other printer, before I knew there was a reverse drive option in marlin.

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insta
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Re: Steppers acting weird

Post by insta » Thu Mar 22, 2018 3:48 am

What about an M502 to reset the EEPROM to the flashed firmware values? Follow it with an M500.
Custom 3D printing for you or your business -- quote [at] pingring.org

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Farr0wn3d
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Re: Steppers acting weird

Post by Farr0wn3d » Fri Mar 23, 2018 12:27 am

Shouldnt reflashing the whole firmware resolve any firmware related issues?

One thing to keep in mind is that you can send the same command 10 times, and a few of those 10 times it will actually work properly. This is for every stepper, not just the extruder.

I totally removed the board, thoroughly inspected it under a magnifying lamp and found nothing out of the ordinary, reinstalled just enough to get one stepper working, and its still acting up.

I ordered a new rambo from ultimachine...

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insta
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Re: Steppers acting weird

Post by insta » Fri Mar 23, 2018 1:06 am

Reflashing doesn't clear the firmware. What's the output of an M503 command?
Custom 3D printing for you or your business -- quote [at] pingring.org

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Farr0wn3d
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Re: Steppers acting weird

Post by Farr0wn3d » Fri Mar 23, 2018 2:21 am

I was not aware...

M503 returns this:
Steps per unit:
M92 X88.88 Y88.88 Z1011.00 E430.00
Maximum feedrates (mm/s):
M203 X200.00 Y200.00 Z25.00 E25.00
Maximum Acceleration (mm/s2):
M201 X1200 Y1200 Z200 E10000
Acceleration: S=acceleration, T=retract acceleration
M204 S2000.00 T10000.00
Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s), Z=maximum Z jerk (mm/s), E=maximum E jerk (mm/s)
M205 S0.00 T0.00 B20000 X15.00 Z0.40 E-1.00
Home offset (mm):
M206 X5.25 Y3.00 Z3.75
PID settings:
M301 P14.72 I1.19 D45.67

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Farr0wn3d
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Location: Calgary, Alberta, Canada

Re: Steppers acting weird

Post by Farr0wn3d » Fri Mar 23, 2018 2:27 am

The M502 command fixed it.

If reflashing doesnt change my firmware, then what does it do?

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Farr0wn3d
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Re: Steppers acting weird

Post by Farr0wn3d » Fri Mar 23, 2018 2:47 am

Reviewing the difference between the settings that were giving me trouble and the ones that were hardcoded has me confused as to where some of those values came from. I have adjusted the steps/mm and the jerk and accel values, but not to the ones that are listed in the settings... Is it possible that changing that extruder steps value fucked with other settings as well?

BTW Thank you very much Insta. Kinda wish I hadnt ordered that new board last night, and that Ultimachine wasnt so prompt in shipping it out... oh well haha

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insta
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Re: Steppers acting weird

Post by insta » Fri Mar 23, 2018 3:38 am

Marlin looks in EEPROM for settings when it boots up. If there's nothing found in EEPROM, then it goes to the hardcoded values in the firmware and loads those instead. When you run an M500 command, the values presently in RAM (regardless of origin) are saved to EEPROM.

Since you changed the values and saved them to EEPROM, even though you changed them in the firmware, Marlin had no reason to go there -- since it found compatible settings in the EEPROM. The M502 command tells Marlin to discard its current values (in RAM) and load from firmware. A subsequent M500 will save the firmware values to EEPROM.
Custom 3D printing for you or your business -- quote [at] pingring.org

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