<p>The developers from the Klipper firmware confirmed that Klipper doesn't care about the native functions of each pin, therefore it is indeed possible to use the expansion pins for controlling (including UART) TMC stepper drivers.</p>

<p>At this point I cannot confirm, but maybe Marlin allows the same by updating the pin assignments in the source code.</p>

CC BY-SA 4.0
2019-11-20T15:46:06.107Z
Marlin does allow so, but you will need to alter the pin declarations. see http://marlinfw.org/docs/hardware/boards.html
Trish
CC BY-SA 4.0
2019-11-20T14:12:24.223Z
2019-11-20T16:25:56.010Z
2019-11-20T16:25:56.010Z
FarO
<p>You can't. In fact, pretty much all boards with directly soldered drivers are not upgradable.</p>

<p>I'd recommend to buy a proper, contemporary, customizable board like the SKR 1.3 for TMCs.
The Fysetc F6 would also work, but uses "custom" connectors and is still AVR based.</p>

CC BY-SA 4.0
2019-11-05T14:18:43.800Z
Since there are still 19 pins available, maybe Klipper firmware can use them. If so I could add three external drivers. If it doesn't work, I can reuse the drivers with the SKR.
FarO
CC BY-SA 4.0
2019-11-20T15:47:19.930Z
you can't *exchange* the drivers if you can't do Surface Mount Soldering, but you can *circumnavigate* them via pins.
Trish
CC BY-SA 4.0
2019-11-04T15:55:33.137Z
2019-11-04T15:55:33.137Z
towe
<p>I have a Printrboard rev. D which includes Allegro A4982 drivers. I would like to replace them, but it appears that newer TMC drivers all require several pins for proper operation.</p>

<p><a href="https://i.sstatic.net/ZnRf5.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/ZnRf5.png" alt="enter image description here"></a></p>

<p>How can I upgrade the drivers in the Printrboard rev. D?</p>

<stepper-driver>
How can I upgrade the drivers in the Printrboard rev. D?
FarO
# How can I upgrade the drivers in the Printrboard rev. D?

(Asked by: username_0 on 2019-10-30)

I have a Printrboard rev. D which includes Allegro A4982 drivers. I would like to replace them, but it appears that newer TMC drivers all require several pins for proper operation.

[![enter image description here](https://i.sstatic.net/ZnRf5.png)](https://i.sstatic.net/ZnRf5.png)

How can I upgrade the drivers in the Printrboard rev. D?

**Tags:** stepper-driver

---

## 2 answers

### Answer by username_0 on 2019-11-20. Score: 1 | Accepted answer

The developers from the Klipper firmware confirmed that Klipper doesn't care about the native functions of each pin, therefore it is indeed possible to use the expansion pins for controlling (including UART) TMC stepper drivers.

At this point I cannot confirm, but maybe Marlin allows the same by updating the pin assignments in the source code.

> **Comments:**
> **username_1**: Marlin does allow so, but you will need to alter the pin declarations. see http://marlinfw.org/docs/hardware/boards.html  

---

### Answer by username_2 on 2019-11-04. Score: 0

You can't. In fact, pretty much all boards with directly soldered drivers are not upgradable.

I'd recommend to buy a proper, contemporary, customizable board like the SKR 1.3 for TMCs.
The Fysetc F6 would also work, but uses "custom" connectors and is still AVR based.

> **Comments:**
> **username_0**: Since there are still 19 pins available, maybe Klipper firmware can use them. If so I could add three external drivers. If it doesn't work, I can reuse the drivers with the SKR.  
> **username_1**: you can't *exchange* the drivers if you can't do Surface Mount Soldering, but you can *circumnavigate* them via pins.  

---

