# Dual / Two z stepper motor for Ender 3 using SKR mini e3 v2
**URL:** https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991
**Category:** General Discussion
**Created:** [December 1, 2023, 2:51pm UTC](https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991 "2023-12-01T14:51:49Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@zwep](https://klipper.discourse.group/u/zwep)
#### Post date: [December 1, 2023, 2:51pm UTC](https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991/1 "2023-12-01T14:51:49Z")
### Basic Information:
Printer Model: Ender 3
MCU / Printerboard: SKR mini e3 V2
`klippy.log`
[klippy.zip](https://klipper.discourse.group/uploads/short-url/zuN9uOo9h69i5OQtdzOXIJuXiwr.zip) (756.0 KB)
### Describe your issue:
Hello,
I want to use a dual z stepper motor on my Ender 3 with SKR mini e3 V2 board. This board has the possibility to drive 2 Z motors (ZAM, ZBM), but Im not sure how to configure it.
My current, single z-motor, config is the following (i.e. the default config provided by klipper)
[stepper\_z]
step\_pin: PB0
dir\_pin: PC5
enable\_pin: !PB1
microsteps: 16
rotation\_distance: 8
endstop\_pin: ^PC2
position\_endstop: 0.0
position\_max: 250
[tmc2209 stepper\_z]
uart\_pin: PC11
tx\_pin: PC10
uart\_address: 1
run\_current: 0.580
stealthchop\_threshold: 999999
From the pinout it seems that both Z motor use the pins PB1 PB0 PC5 for Enable/Step/Dir. However, when I configure a [stepper\_z1] with those pins I get an error that those pins are already used.
I face a similar situation when defining the [tmc2209 stepper\_z1], but then concerning the uart\_address. I know that the uart\_pin and tx\_pin are all the same, but the uart\_address should be unique. Since this number can only be 0, 1, 2 and 3, and since all of these are already given to motor x, y, z, and e, I think I should also re-use the uart\_address for the second z motor.
Besides, it is a very desirable property to control motor z and motor z1 in exactly the same way of course.
Can someone guide or give me the correct config for a second z motor? Also if I have not provided sufficient information, please let me know
---
### Author:  [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)
#### Post date: [December 1, 2023, 5:10pm UTC](https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991/2 "2023-12-01T17:10:14Z")
Hello @zwep !
You can find information here:
[https://www.klipper3d.org/Config\_Reference.html#stepper\_z1](https://www.klipper3d.org/Config_Reference.html#stepper_z1)
---
### Author:  [@zwep](https://klipper.discourse.group/u/zwep)
#### Post date: [December 1, 2023, 5:34pm UTC](https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991/3 "2023-12-01T17:34:14Z")
Hello,
thank you for you answer. I am aware of that page and that helped me to give at least the required syntax for the definition of the second z stepper motor. However, this does not tell me what to do if the pins are the same, or how to deal with the uart\_address overlap.
---
### Author:  [@Sineos](https://klipper.discourse.group/u/Sineos)
#### Post date: [December 1, 2023, 5:58pm UTC](https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991/5 "2023-12-01T17:58:31Z")
> [@zwep](#):
>
> However, this does not tell me what to do if the pins are the same, or how to deal with the uart\_address overlap.
You do not need a second z-stepper configuration in your printer.cfg. The two z-stepper ports in this board are wired in parallel and driven by the same TMC
- Remove the z1 from your cfg
- Remove the z1 TMC configuration
- Double the run\_current to what you typically need for one of your steppers
---
### Author:  [@zwep](https://klipper.discourse.group/u/zwep)
#### Post date: [December 1, 2023, 8:44pm UTC](https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991/6 "2023-12-01T20:44:50Z")
Ah great, thanks! That explains a lot.
I now remember looking at an Anet A8 config with the SKR mini… but I was surprised that it did not have a definition for the second z stepper motor. Didnt think much of it, and attributed it to an error…
Anyway, thanks again 🙂
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### Author:  [@system](https://klipper.discourse.group/u/system)
#### Post date: [January 1, 2024, 6:45am UTC](https://klipper.discourse.group/t/dual-two-z-stepper-motor-for-ender-3-using-skr-mini-e3-v2/11991/7 "2024-01-01T06:45:45Z")
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