SKR v1.4 with TMC2209 do I really clip the StallGuard pin?

What is the problem?

I had my Ender3 SKR mini board die recently and was recommended that the big brother boards are a good upgrade that would prevent major hassles if it happens again. I just received my new SKR V1.4 and TMC2209 driver boards and have been reviewing the manual and other documents to understand the setup. One of the sections indicates that if StallGuard is not used, that one of the pins on the TMC2209 must be permanently cut off. Since I'm not currently planning on using sensorless homing, I could do that. However, I may want to use it in the future. That seems like an awful way to lock myself into a configuration without knowing any better.

The hitch here may be that I plan to use Klipper so it won't be the standard Marlin FW so perhaps I should ask there? I already had the other thread but decided it wasn't exactly related so I opted to ask in a new topic. I can ask on the Klipper forum if that's deemed more appropriate.

What did you already try to solve it?

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Have you tried running in safe mode?

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Did running in safe mode solve the problem?

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Systeminfo Bundle

You can download this in OctoPrint's System Information dialog ... no bundle, no support!)

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Additional information about your setup

OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible

Ender3
RPi3B
OctoPrint
Klipper

Another option according to BTT github is to rewire the end stop switches to pull high instead of low. Apparently that would work since the DIAG pin pulls low thus breaking the function of the existing end stop. That seems like a much better solution as otherwise deciding to go with sensorless homing down the road would require removing the jumper pins and soldering on new ones.

Just bend the pin back a little and then put on the board

That's a better option than cutting. I'll have to check if there will be a potential short in any bend direction. Seems like there should have just been a jumper or switch on the top side somewhere to connect/disconnect DIAG so this wouldn't be needed. Or at least when they made the EZ adapter it could have been on the adapter.

It's an oversight in the board design. Or BTT just assumed you'd want to use sensorless if it was available :man_shrugging:.

There are other boards, like the Octopus, that have jumpers for that very reason.

I may consider using sensorless homing for x and y because even if there was an error of 1-2mm I'd only lose some bed space. But for z that error could be problematic for obvious reasons. I suspect it might be ok for dual-z gantry leveling (running into the top for example) but cutting the pin means it cannot be used interchangeably. Seems like a major minor problem considering shipping times. If i could drive to the local RadioShack and pick up a replacement same day this would be a non issue.

Also, cutting the pin on the bottom of the driver doesn't negate you from using sensorless homing at all either. The driver should have also come with a jumper cable that can be used to connect the diag pins on top of it directly to the appropriate end stop connector.

That's how you'd use it with boards that don't have the pins directly wired to the endstop pin anyway. So if it really comes down to that, you wouldn't have to replace it.

Also, don't use it for Z. It's not accurate enough, even with dual z.

So if i understand, cut the pin for now on all drivers. Then, if i choose to try sensorless homing down the road, i add a jumper from the top diag pin to the appropriate x- or y-stop jumper?

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