Stallguard and endstop with tmc2209
-
I am running reprap firmware and tmc2209 drivers for all motors. As far as I know, when sensorless homing is enabled the endstop pins are not usable anymore. So I was wondering, could you connect the endstop to other pins, do regular homing, and then still have stallguard available to detect skipped steps during a print?
-
@justGuner What board are you using?
-
@gloomyandy It's a SKR 2 (BigTreeTech)
-
@justGuner On the skr2 there is a jumper under the driver that when in place connects the the diag output to the corresponding endstop see: https://teamgloomy.github.io/skr_2.0_general.html#driver-diag-pin Note that if you want to use sensorless homing or stall detection on that driver you will need to also make an entry in the board.txt file see: https://teamgloomy.github.io/skr_2.0_sensorless.html#boardtxt-changes
You are correct in that if you enable stall detection (or sensorless homing) on a driver then you cannot use the corresponding endstop pin. You can however use any other free endstop pin instead. So for instance you could use E0DET or E1DET and then stil use stall detect on X and Y. However stall detect can be tricky to setup (I'd say harder than sensorless homing) as you don't want any false triggers, so I'm not sure if it really gans you very much. Also if you are going to go to the trouble of setting up stall detect then you will pretty much get sensorless homing for free, so you might want to just use that.
-
@gloomyandy I realise that I can use sensorless homing, but from what I've read it is much more innacurate than regular endstops. And in case of a missed step during a print, I think it would be better to do homing with the more precise method, rather than having it home, still be off a bit, and continue printing.
-
@justGuner I don't think I've ever had a problem with missed steps during a print that hasn't also been part of a much bigger problem (so recovery was not an option). I've also found that sensorless homing is more than accurate enough to operate my e3d toolchanger (which needs pretty accurate and repeatable homing to be able to pick up and drop off tools). I think the reports of problems with accuracy are somewhat overstated. Honestly I think you are more likely to have issues with false triggers from stall detection during a print (especiially if you want to operate at higher speeds), but I guess only you know what will be best with your setup. Certainly the simplest setup would just be to use endstops and ignore stall detection completely! Good luck!
