# TMC2208: periodically gets errors while homing **URL:** \ **Category:** General Discussion\ **Created:** [April 29, 2021, 11:46am UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209 "2021-04-29T11:46:44Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![erin](https://avatars.discourse-cdn.com/v4/letter/e/67e7ee/32.png) [@erin](https://klipper.discourse.group/u/erin)\ **Post date:** [April 29, 2021, 11:46am UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/1 "2021-04-29T11:46:44Z")
Hello everybody! I have a problem after installing TMC2208 drivers with UART connection. I tried to figure it out on my own but couldn’t find a solution. I really hope for the help of the community. Periodically, homing is interrupted by an error. Errors occur only on homing, and never during printing. They are of two types: ``` 11:55:53 Failed to home a: Timeout during homing 11:55:58 Unable to read tmc uart 'stepper_b' register GSTAT Once the underlying issue is corrected, use the "FIRMWARE_RESTART" command to reset the firmware, reload the config, and restart the host software. Printer is shutdown 11:55:58 Unable to read tmc uart 'stepper_b' register GSTAT 12:07:27 Failed to home b: Timeout during homing 12:07:32 Unable to read tmc uart 'stepper_b' register IFCNT 12:07:32 Unable to read tmc uart 'stepper_b' register IFCNT Once the underlying issue is corrected, use the "FIRMWARE_RESTART" command to reset the firmware, reload the config, and restart the host software. Printer is shutdown ``` Axes can be any: stepper\_a, stepper\_b or stepper\_c. 1. I have tested the UART connection to the board many times. 2. I tried to change the uart\_pin of the drivers among themselves. 3. Changed the drivers themselves in places in a board. 4. I tried to decrease and increase the current in the settings. 5. Tried setting stealthchop\_threshold to 0 and 999999. The only thing that helps is decreasing homing\_speed to 10. In this case, errors crash much less often. Somebody tell me what could be the problem? I’m ready to give up, re-solder the cut pins and connect the drivers without UART… Printer: Anycubic Kossel (delta) Board: Trigorilla 1.3 I installed the drivers according to this guide: [Anycubic Kossel Klipper Trigorilla TMC Driver UART Upgrade - Lukas Pomykal](https://www.lpomykal.cz/anycubic-kossel-klipper-trigorilla-tmc-driver-upgrade/) ---
**Author:** ![erin](https://avatars.discourse-cdn.com/v4/letter/e/67e7ee/32.png) [@erin](https://klipper.discourse.group/u/erin)\ **Post date:** [April 29, 2021, 11:52am UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/2 "2021-04-29T11:52:53Z")
Here is a klippy.log with a couple of such errors, search by: ``` Timeout during homing ``` > **[Starting Klippy...Args: \['/home/pi/klipper/klippy/klippy.py', '/home/pi/printe...](https://pastebin.com/QDruCgrC)** > > Pastebin.com is the number one paste tool since 2002. Pastebin is a website where you can store text online for a set period of time. ---
**Author:** ![LazaroFilm](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/lazarofilm/32/21_2.png) [@LazaroFilm](https://klipper.discourse.group/u/LazaroFilm)\ **Post date:** [April 29, 2021, 3:24pm UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/3 "2021-04-29T15:24:59Z")
What does `DUMP_TMC STEPPER=stepper_b` return? You can also try to reinitiallize the stepper with `INIT_TMC STEPPER=` ---
**Author:** ![erin](https://avatars.discourse-cdn.com/v4/letter/e/67e7ee/32.png) [@erin](https://klipper.discourse.group/u/erin)\ **Post date:** [April 30, 2021, 3:05am UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/4 "2021-04-30T03:05:30Z")
``` Send: G28 Recv: // Klipper state: Shutdown Recv: !! Failed to home a: Timeout during homing Recv: ok [...] Send: G28 Recv: // Unable to read tmc uart 'stepper_b' register IFCNT Recv: // Once the underlying issue is corrected, use the Recv: // "FIRMWARE_RESTART" command to reset the firmware, reload the Recv: // config, and restart the host software. Recv: // Printer is shutdown Recv: !! Unable to read tmc uart 'stepper_b' register IFCNT Recv: ok [...] Send: DUMP_TMC STEPPER=stepper_b Recv: // Unable to read tmc uart 'stepper_b' register IFCNT Recv: // Once the underlying issue is corrected, use the Recv: // "FIRMWARE_RESTART" command to reset the firmware, reload the Recv: // config, and restart the host software. Recv: // Printer is shutdown Recv: !! Unable to read tmc uart 'stepper_b' register IFCNT Recv: ok [...] Send: INIT_TMC STEPPER=stepper_b Recv: // Unable to read tmc uart 'stepper_b' register IFCNT Recv: // Once the underlying issue is corrected, use the Recv: // "FIRMWARE_RESTART" command to reset the firmware, reload the Recv: // config, and restart the host software. Recv: // Printer is shutdown Recv: !! Unable to read tmc uart 'stepper_b' register IFCNT Recv: ok ``` > **[Starting Klippy...Args: \['/home/pi/klipper/klippy/klippy.py', '/home/pi/printe...](https://pastebin.com/JpRr2BzE)** > > Pastebin.com is the number one paste tool since 2002. Pastebin is a website where you can store text online for a set period of time. ---
**Author:** ![koconnor](https://avatars.discourse-cdn.com/v4/letter/k/aca169/32.png) [@koconnor](https://klipper.discourse.group/u/koconnor)\ **Post date:** [May 2, 2021, 4:45pm UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/5 "2021-05-02T16:45:09Z")
FYI, there is some information on that error message at: [https://www.klipper3d.org/TMC\_Drivers.html#i-keep-getting-unable-to-read-tmc-uart-stepper\_x-register-ifcnt-errors](https://www.klipper3d.org/TMC_Drivers.html#i-keep-getting-unable-to-read-tmc-uart-stepper_x-register-ifcnt-errors). If you’re getting the error sporadically, I’d look for loose or noisy uart wiring. -Kevin ---
**Author:** ![erin](https://avatars.discourse-cdn.com/v4/letter/e/67e7ee/32.png) [@erin](https://klipper.discourse.group/u/erin)\ **Post date:** [May 3, 2021, 2:58pm UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/6 "2021-05-03T14:58:42Z")
I checked the UART connection again and, just in case, replaced the wires with others. Nothing has changed. As a result, I was finally tired of it and I connected the drivers without UART. I can assume that the reason may be in my Trigorilla board. Perhaps I will try to change it to another board for verification. Maybe later. ---
**Author:** ![massild](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/massild/32/169_2.png) [@massild](https://klipper.discourse.group/u/massild)\ **Post date:** [June 10, 2021, 10:14pm UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/7 "2021-06-10T22:14:41Z")
I have the same issue after an upgrade to 0.9.0. I was on 0.8.0 and it worked fine for months. ---
**Author:** ![massild](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/massild/32/169_2.png) [@massild](https://klipper.discourse.group/u/massild)\ **Post date:** [June 10, 2021, 11:04pm UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/8 "2021-06-10T23:04:02Z")
Kevin, I am experiencing the same issue. I am running an MKS Gen L board with TMC2208 drivers. The error occurs during the home operation to 5 layers into the print. It is also firmware specific. 0.8.0 runs the TMC2208 in UART mode without issue. I have a second board that I still had old firmware on and it worked. As soon as I upgraded to 0.9.0 that board also did not work. I hope this is helpful information. ---
**Author:** ![koconnor](https://avatars.discourse-cdn.com/v4/letter/k/aca169/32.png) [@koconnor](https://klipper.discourse.group/u/koconnor)\ **Post date:** [June 11, 2021, 2:13am UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/9 "2021-06-11T02:13:27Z")
The Klipper software was recently changed to periodically check driver status (whenever the stepper motor is enabled). If Klipper can’t contact the stepper motor driver it will report an error. I would double check that none of the UART wires are loose or frayed. -Kevin ---
**Author:** ![massild](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/massild/32/169_2.png) [@massild](https://klipper.discourse.group/u/massild)\ **Post date:** [June 11, 2021, 2:27am UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/10 "2021-06-11T02:27:05Z")
Excellent insight. Thank you. ---
**Author:** ![EddyMI3D](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/eddymi3d/32/1981_2.png) [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)\ **Post date:** [November 4, 2025, 2:30pm UTC](https://klipper.discourse.group/t/tmc2208-periodically-gets-errors-while-homing/209/11 "2025-11-04T14:30:04Z")