Sensorless homing X returns Unhandled exception during run

General Discussion
1

Basic Information:

Printer Model: Voron Switchwire
MCU / Printerboard: BTT E3 SKR MINI V3.0
klippy.log

Hello.
I am trying to use sensorless homing to home X on my Switchwire converted ender 3-pro.
i followed the guide in the documentation, added the jumpers to the board for the diag pin, changed printer.cfg and when i run G28 X0 the printer halts and displays “Unhandled exception during run”. Found one on Reddit with the same problem but no solution. Anybody have any poiters to where i can start to look for something wrong?

I have changed back to using the switch now, so the last entry’s in the klipper-log is with that config.
sensorless config starts here

2

First step would be to remove the unofficial extensions, make sure to have the latest Klipper main-line, and then retry.
Please attach any log file here by just dragging and dropping it to the post.

3

What do you mean by unofficial extensions? Kamp and led-effekts?

4 
Untracked files: klippy/extras/led_effect.py
Branch: master
Remote: origin
Tracked URL: https://github.com/Klipper3d/klipper.git

KAMP is just a macro, but when troubleshooting it makes sense to remove as much “potentially interfering stuff” as possible

5

klippy.log (127.6 KB)
Fresh install of raspian lite, klipper,moonraker and mainsail.

samme error.

6 
[tmc2209 stepper_x]
uart_pin = PC11
tx_pin = PC10
driver_sgthrs = 150             # <------------
uart_address = 0
run_current = 0.580
interpolate = false
stealthchop_threshold = 0
diag_pin = ^PC0

Have you tried it with

driver_SGTHRS

?

7

the config file has caps

[tmc2209 stepper_x]
uart_pin: PC11
tx_pin: PC10
uart_address: 0
run_current: 0.580
interpolate: false
stealthchop_threshold: 0
diag_pin: ^PC0 # Set to MCU pin connected to TMC DIAG pin
driver_SGTHRS: 150 # 255 is most sensitive value, 0 is least sensitive

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8

Is the tx_pin really needed when uart_pin and uart_Address are populated?
I mean if the names are wrong the Klipper syntax checker will raise an error after reboot.

9

yep, not happy with that. klipper said because of shared uart pins you need tx_pin

10

That is strange that Klipper is insisting on a tx_pin.

Could you post your printer.cfg and comment out the “tx_pin” statements and post a screenshot of the Klipper error?

11

did not realize you had to comment out all of them. that worked fine.
printer.cfg (7.6 KB)

No help for the shutdown when G28 X0

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12

At least an optimization of your config.
Can you reduce homing speed of Y and X to 50 mm/s or even less at least for testing purpose?
In the printer.cfg the tx_pins are still active.
Argh just saw it is a CoreXZ and the respective axes are set up accordingly… :confused:

13

iknow, because i fetched the config, then i tested the no tx_pins.
My X home is 20, don’t understand what the homing speed of Y has to do with this.

14

Just looking at your printer.cfg file - why do you have 64 microsteps for stepper_x and 32 for stepper_y?

I haven’t seen somebody mix sensorless homing on X and a microswitch on Y before - it looks like you had a microswitch on X before; can you go back to it and see what happens?

15

The diffrent microsteps is from testing “spreadCycle” vs “stealthChop”
I have microswitch on X, works just fine with that. its a working printer. but i want sensorless on X because of cable mess.

16

It is a CoreXZ. Did notice it after my post.
But sensorless homing for Z is not recommended.

17

I hear you on that one. Any chance you can go with sensorless on Y?

Could you try the same number of microsteps (I would suggest 32) for the X & Y steppers?

18

changed the microsteps to 32 for both,no change.
the sensorless Y i can check tomorrow. not keen on flip the printer on it’s side tonight.

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19

Sensorless on Y works. does klipper not like sensorless in CoreXZ.

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20

It was my [safe_z_home] it had z_hop:10 in it. it works after i set it to 0

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