Weird halfing steps with Marlin on SKR V1.3 / 8825

I have installed Marlin on my SKR (after first trying Smoothieware until recognizing that it won’t work) with 8825 Pololus. So I got my next stumble stone: the stepping is halfed more or less at random. Or so it looks like. I made manual tests and all moved as it should. But then after doing a print job the steps (in most directions) are halfed. Sometimes XYE sometimes YZE or only Z (I only see it in the print result). So far I got no idea what could be the reason for this.

I doubt the firmware is changing so the next step is too look at the jumpers on the drivers. These jumpers will usually have one row of pins grounded and the jumper connects ground to the 3(?) micro-stepping signals. If jumpers are loose there could be problems during operation or maybe there is a very poor ground causing the drivers to change the settings.

Because it’s happening across many drivers I might look to see that your power and ground to the board is solid and stable.

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I was thinking about the jumpers too and will experiment in that area. Stil, it’s puzzling. Nothing just goes straight the line :slight_smile:

Turned out it were just the jumpers. More or less I plugged in the drivers with the board factory settings. I should have taken some time there, but try and error is still the most common practice :wink:

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even the drivers with digital micro-stepping control require specific jumpers in place unless the board is specifically pre-populated with the drivers. FYI, the TMC2209 steppers are crazy quiet and run the motors very cool compared to 4988 and 8825.

Thanks, I’ll remember this! For the time being I go with the 8825 since they are just there and do the job. This is my 2nd printer. The first I built completely from scratch with lots of wooden parts. I tuned it over time with self printed parts and learned a lot. My 2nd printer (which now got it’s first test prints) was “stolen” from a free design which I re-designed with FreeCAD (which I had to learn first). It’s where the print head it dragged passively (don’t know what that design is called). But what a difference to my old printer! Tedious sometimes but great fun overall. And the result it really rewarding!