# Unable read tmc uart 'stepper\_z' register IFCNT **URL:** \ **Category:** General Discussion\ **Created:** [April 26, 2024, 7:10am UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045 "2024-04-26T07:10:18Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Alex\_117](https://avatars.discourse-cdn.com/v4/letter/a/50afbb/32.png) [@Alex\_117](https://klipper.discourse.group/u/Alex_117)\ **Post date:** [April 26, 2024, 7:10am UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045/1 "2024-04-26T07:10:18Z")
Good afternoon! I encountered this error. It appeared after the end of printing. Absolutely all 5 stepper motor drivers do not work. I replaced the board and drivers, as well as the power supply, because they were available. I printed another file and exactly at the end of printing this error occurred again. A different board, a different configuration, and everything also gives this error. I don’t understand why it happens and how to fix it. I found many similar topics with such a problem, but I did not find a solution to it. In step/dir mode, the drivers are working, from which I conclude that the problem is in the klipper code. Has anyone managed to fix this error? Thank you in advance! [work printer.cfg](https://klipper.discourse.group/uploads/short-url/db24D9VuUQDRcGWkq42AzPpDMvV.cfg) (9.0 KB) ---
**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:** [April 26, 2024, 7:40am UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045/2 "2024-04-26T07:40:25Z")
Please stick to the template (and don’t delete it) and post the klippy.log > [@Alex\_117](#): > > I replaced the board and drivers, It would help to tell us what board you use (was also asked in the template) > [@Alex\_117](#): > > Absolutely all 5 stepper motor drivers do not work. Have you set up the board for driver UART mode? * * * ```auto [tmc2208 stepper_z] # <- is this by intension a tmc2208? uart_pin: PE0 run_current: 1.000 hold_current: 0.800 interpolate: True stealthchop_threshold: 120 #diag_pin: ``` ---
**Author:** ![Alex\_117](https://avatars.discourse-cdn.com/v4/letter/a/50afbb/32.png) [@Alex\_117](https://klipper.discourse.group/u/Alex_117)\ **Post date:** [April 26, 2024, 10:05am UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045/3 "2024-04-26T10:05:14Z")
Board - BigTreeTech SKR2. Drivers - tmc2209. There is nothing criminal in the log file. There’s a regular printing cycle. When I put it to print again, that’s when this error crashes. I’ll attach the log a little later (I’m going to buy new drivers). Drivers in uart mode. On one of the axes 2208, then 2209 everywhere. ---
**Author:** ![Alex\_117](https://avatars.discourse-cdn.com/v4/letter/a/50afbb/32.png) [@Alex\_117](https://klipper.discourse.group/u/Alex_117)\ **Post date:** [April 26, 2024, 10:08am UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045/4 "2024-04-26T10:08:02Z")
Please tell me, does the abbreviation “IFCNT” stand for? ---
**Author:** ![mykepredko](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/mykepredko/32/2085_2.png) [@mykepredko](https://klipper.discourse.group/u/mykepredko)\ **Post date:** [April 26, 2024, 2:31pm UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045/5 "2024-04-26T14:31:29Z")
“Interface transmission counter” - it is updated every time serial data is received. Klipper reads it back to confirm that it is successfully communicating with the TMC2208. When posting a question, **ALWAYS** follow the template and include all requested data including the `klippy.log`. ---
**Author:** ![Alex\_117](https://avatars.discourse-cdn.com/v4/letter/a/50afbb/32.png) [@Alex\_117](https://klipper.discourse.group/u/Alex_117)\ **Post date:** [April 27, 2024, 5:26pm UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045/6 "2024-04-27T17:26:14Z")
We managed to sort out the problem. On the skr2 board, when connecting the rgb address tape, there is a strong drawdown along the 5 volt line, which causes a lack of power for the driver logic. When you turn off the rgb tape, everything returns to normal. Thank you very much for your advice! ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/klipper/original/1X/64419bf2aac6639e6ef5cef200dcd456b0a01ac3.png) [@system](https://klipper.discourse.group/u/system)\ **Post date:** [May 28, 2024, 3:26am UTC](https://klipper.discourse.group/t/unable-read-tmc-uart-stepper-z-register-ifcnt/16045/7 "2024-05-28T03:26:36Z")
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