Guía completa SKR v1.4/v1.4 Turbo con drivers TMC Sensorless y Display TFT35 V3.0
Guía completa SKR v1.4/v1.4 Turbo con drivers TMC Sensorless y Display TFT35 V3.0

Complete guide SKR v1.4 / v1.4 Turbo with TMC2209 Sensorless drivers and Display TFT35 V3.0

Lately the new electronic boards of the company BigTreeTech (SKR V1.4 and SKR 1.4 Turbo) are enjoying quite a notoriety within the world of 3D printing. And it is not surprising, since they have perfectly understood the “Maker” movement and have adapted to the needs of users and potential clients.

Having different sockets for all types of displays, specific BLTouch/3DTouch connectors, ease of use with TMC drivers without external wiring, specific connectors for LED strips, removable protection fuses and a few other things are just some examples of how it has targeted BigTreeTech the market quite successfully.

In fact, in our Telegram channel of 3DWork often enough people with this type of electronics enter to ask questions. So I had in mind for some time to prepare a guide to configure Marlin 2.x with SKR v1.4 / SKR v1.4 Turbo electronics + TMC2209 Sensorless drivers. And, of course, its splendid TFT35 V3.0 hybrid display, which seems to me a real virgin if I am honest.

So let’s get to it without further delay. And don’t forget to add us to our social networks (Facebook, Twitter, Instagram), this way you will support the 3DWork project.



Introduction to SKR electronics

SKR V1.4Turbo 1

In today’s article we are going to focus on how to configure our SKR V1.4 / V1.4 Turbo electronics, along with TMC2209 Sensorless drivers and the new hybrid TFT35 V3.0 display.

Sensorless, in case you don’t know, means not putting mechanical limit switches on the X and Y axes. Modern TMC2209 drivers allow us to perform this function and save us time, money and unnecessary wiring.

In fact, if you already have these limit switches, you can use them as filament cut sensors. So at least you could give a new utility and it would not be left in the forgotten drawer.

I am aware that you may not have the same display or your drivers are different. However, even if this were the case, quite a part of the article will be useful to you, and you only have to skip the component and find your own configuration.

Also, if you feel like it, you can always visit us at our Telegram channel, and if the necessary information is not documented help us complete the article to facilitate the same process for other users.


Technical specifications and connections

SKR v1.4 and v1.4 Turbo boards have an exact size of 110 x 85mm (102 x 76mm between holes). Their architecture is ARM Cortex-M3 (CPU) and they can be powered interchangeably at 12V and 24V (5A-15A).

They have a connector for WiFi modules ESP-01S, can use different communication modes for their drivers (SPI, UART and STEP / DIR) and support X, Y, ZAM, ZBM, E0 and E1 motors.

Then I leave you some official images of the manufacturer where you can see all the connections and sockets of the electronic v1.4 and v1.4 Turbo.

Esquema electrico SKR2

Esquema electrico SKR


Comparison between SKR V1.3, V1.4 and V1.4 Turbo


The differences are more marked when we compare a SKR v1.3 electronics with its higher versions v1.4 and v1.4 Turbo. As you can see in the image above, the latest electronics add quite interesting functions. Double interface for the Z axis, support for external power modules, support for LED strips, and some other things.

If we only compare the last two models, the only thing that differentiates the SKR v1.4 electronics from the v1.4 Turbo is that it has a superior microcontroller. In the v1.4 model we can find a 100 Mhz ARM Cortex-M3 micro, while in v1.4 Turbo the micro it presents can reach frequencies of up to 120 Mhz. This is certainly a remarkable 20% increase in process speed, which is no small feat.



In this other table you can see another comparison on different aspects of the electronic v1.3 and v1.4 / v.14 turbo, mainly the possibility of communication via WiFi.

This requires a specific module for this task, and transmission speeds are certainly quite low. Sending a GCode of some megabytes can get you desperate, so at this point it is more advisable to use a Raspberry Pi with Octoprint for such a task.

If you do not know what Octoprint is and the possibilities it can offer you, I recommend you read the article Octoprint: Manage your 3D printer remotely with Raspberry Pi and Octopi

However, although these tables extracted from official SKR support indicate that it does not have WiFi support, this does not in any way imply that you cannot install one if you wish. It simply means that the v1.3 versions do not have a specific port to connect them to, but you could plug your WiFi module into the TFT connector and remap it into Marlin (for example).


Necessary components

Here I leave you some of the components that appear in today’s article. It is my duty to inform you that they are affiliate links to different online marketplaces online stores.

If by chance you use them, the price of the product will be the same as if you access regularly. And 3DWork will have a small commission left to help maintain this website.

SKR v1.4  Amazon Logo PNG e1579685453346 aliexpress logo banggood
SKR v1.4 Turbo  Amazon Logo PNG e1579685453346 aliexpress logo banggood
BTT TMC2209 v1.2 Amazon Logo PNG e1579685453346 aliexpress logo banggood
MKS TMC2209 v1.0 Amazon Logo PNG e1579685453346 banggood
MKS TMC2209 v2.0 aliexpress logo banggood
FYSETC TMC2209 v3.0 Amazon Logo PNG e1579685453346 aliexpress logo banggood
ERYONE TMC2209 v3.0 Amazon Logo PNG e1579685453346

Or if you wish, you can use our component search engine, where you can compare prices in different Marketplaces (Amazon, Aliexpress, Banggood, etc.) with a single search and very easily.



Preparing the project

Visual Studio Code

Actualiza tu impresora 3D a Marlin 2.x.x con Visual Studio Code y

Before starting to edit Marlin, I recommend that you install a good code editor. For this purpose, the ideal – and recommended by me – is that you install Visual Studio Code. Not only is it a powerful code editor, but it also has a large number of extensions, and you can even compile Marlin directly from it.

Visual Studio Code can be freely downloaded (completely free) from your project’s website at next link. And once you have edited Marlin and the necessary parameters – which you will find a little later – you can compile it and upload your new firmware to the printer.

In this article you can find more information on how to correctly compile your new Marlin firmware and upload it directly to your printer: Configure and update your 3D printer using Visual Studio Code and


Downloading Marlin 2.x

Guía completa para configurar Marlin 2.0.x desde cero y no morir en el intento

The next thing you should do, of course, is download the Marlin sources – or source code – to your computer. To do this we will go to its official website and access the download section.

Here I leave you the direct link, to that you can save some time. I usually download the firmware LATEST RELEASE, just below the word DOWNLOAD. There, click on the link, which is the one available today for version

Please note, however, that new updates and revisions are released regularly. So it is possible that when you read this article there is a higher version and its name is different. In that case it would not be a major problem, download the latest version and that’s it.

Another option is to download the version of the manufacturer Bigtreetech, although I do not know the configuration that will be established and of course it will not adapt to the mechanics of your machine. Firmwares are available on Github at next link.


Using 3DWork Marlin Builder


Although, in the previous section we recommend you download Marlin directly from the official page, you can also use our Marlin Builder that we prepared some time ago in 3DWork.

Marlin Builder offers you two possibilities. The first is to directly configure the firmware with the desired parameters from your browser and download it later. In this way, you will save a lot of work in this regard and then you will only have to finish configuring your SKR electronics with TMC drivers with the information in this article.

Marlin builder 2

The second option Marlin Builder offers you to download a series of pre-configured firmwares officially offered by Marlin. I personally would search between manufacturers and firmwares if your printer exists and I would use it as a base, since it will be absolutely everything previously configured.

Then you just have to follow the instructions in this article and you can enjoy your new electronics quickly. You simply have to select the brand and model from a dropdown and press the download button (see image above).


Check the board supply (12V / 24V)

Jumper SKR VDD

If you look closely, there is a jumper in the central part of our SKR v1.4 and v1.4 Turbo electronics that indicates the way of feeding the board.

Before connecting your electronics you must select the power that you are going to supply to your board correctly (5V USB or 12 / 24V VDD). If you are going to power the board from a USB cable, you must choose the USB option, and if you use a power supply, the VDD option.

My electronics is connected to my 24V power supply, so I choose the VDD option as you can see in the image above (click to enlarge)

Another important detail is that the SKR electronics support 12V or 24V. Regardless of the power source you use, you should always use components that match it.

If your power supply is 24V, the fans you use must be 24V (otherwise you can irreparably damage them). Probably it was not necessary to remember it but it never hurts, since there are several components to consider.


Configuring the firmware (Marlin)

Marlin 12

Before starting with the Marlin configuration, if you are starting from scratch to prepare your new firmware, I recommend that you read this other article before: Complete guide: Set up Marlin 2.0.x from scratch and not die trying.

The reason is that in this article I am only going to explain how to configure the SKR v1.4 and SKR v.14 Turbo electronics to use all the power that the TMC2209 (Sensorless) drivers offer us, configuring themselves “intelligently” and their “hybrid” display TFT35 v3.0

The rest of the components of the printer such as the number of extruders, speeds, printer size, temperature parameters and many other things we already explained previously in the article that I indicated a few lines above (Complete guide of Marlin).

It wouldn’t make much sense deploying again all that information here as we will duplicate content without any need. Well clarified this point … Let’s start!


Modifying “Platformio.ini” file

The first file that we are going to modify is the “Platformio.ini” to indicate to our compiler what type of microprocessor we have in our electronics. If we do not indicate it Visual Studio Code you would have problems compiling our firmware.

This file is located inside the Marlin firmware, exactly in the root directory. Here you have the values ​​depending on which of the two we are going to install on your printer.

Electronic board type ENV_DEFAULT
SKR v1.4 LPC1768
SKR v1.4 Turbo LPC1769

Already knowing what values ​​we have to use, we will edit “Platformio.ini” and in the field “env_default” we will put the chord to our electronics. In my case I have a v1.4 Turbo so I directly added “LPC1769

src_dir = Marlin
boards_dir = buildroot/share/PlatformIO/boards
default_envs = LPC1769
include_dir  = Marlin


Modifying “Configuration.h” file

Once the microprocessor type of our electronics is configured in Visual Studio Code, we proceed to modify the two files that are necessary in Marlin.

We will start with the parameters to configure the communication ports (main and secondary) and the communication speed. In this last parameter I usually put 250,000bds but if you experience any problem, use 115,200bds.

* Select the serial port on the board to use for communication with the host.
* This allows the connection of wireless adapters (for instance) to non-default port pins.
* Serial port -1 is the USB emulated serial port, if available.
* Note: The first serial port (-1 or 0) will always be used by the Arduino bootloader.
* :[-1, 0, 1, 2, 3, 4, 5, 6, 7]
#define SERIAL_PORT 0

* Select a secondary serial port on the board to use for communication with the host.
* :[-1, 0, 1, 2, 3, 4, 5, 6, 7]
#define SERIAL_PORT_2 -1
* This setting determines the communication speed of the printer.
* 250000 works in most cases, but you might try a lower speed if
* you commonly experience drop-outs during host printing.
* You may try up to 1000000 to speed up SD file transfer.
* :[2400, 9600, 19200, 38400, 57600, 115200, 250000, 500000, 1000000]
#define BAUDRATE 250000


Now we are going to tell Marlin exactly what type of electronic board our printer has. I leave you a list here of the different SKR models and on your right the parameters that you must enter:

Electronic board type Parameter

I have a v1.4 Turbo, so I indicate it to Marlin as follows:

// Choose the name from boards.h that matches your setup


Then we will configure the type of driver we have and the motors on which they are mounted. We will look for the following lines and add them to it. You have a multitude of different drivers, so if yours was not TMC2209 change it for the one you are going to install.

* Stepper Drivers
* These settings allow Marlin to tune stepper driver timing and enable advanced options for
* stepper drivers that support them. You may also override timing options in Configuration_adv.h.
* A4988 is assumed for unspecified drivers.
* Options: A4988, A5984, DRV8825, LV8729, L6470, L6474, POWERSTEP01,
*          TB6560, TB6600, TMC2100,
*          TMC2130, TMC2130_STANDALONE, TMC2160, TMC2160_STANDALONE,
*          TMC2208, TMC2208_STANDALONE, TMC2209, TMC2209_STANDALONE,
*          TMC26X,  TMC26X_STANDALONE,  TMC2660, TMC2660_STANDALONE,
*          TMC5130, TMC5130_STANDALONE, TMC5160, TMC5160_STANDALONE
* :['A4988', 'A5984', 'DRV8825', 'LV8729', 'L6470', 'L6474', 'POWERSTEP01', 'TB6560', 'TB6600', 'TMC2100', 'TMC2130', 'TMC2130_STANDALONE', 'TMC2160', 'TMC2160_STANDALONE', 'TMC2208', 'TMC2208_STANDALONE', 'TMC2209', 'TMC2209_STANDALONE', 'TMC26X', 'TMC26X_STANDALONE', 'TMC2660', 'TMC2660_STANDALONE', 'TMC5130', 'TMC5130_STANDALONE', 'TMC5160', 'TMC5160_STANDALONE']
#define X_DRIVER_TYPE  TMC2209
#define Y_DRIVER_TYPE  TMC2209
#define Z_DRIVER_TYPE  TMC2209
//#define X2_DRIVER_TYPE A4988
//#define Y2_DRIVER_TYPE A4988
//#define Z2_DRIVER_TYPE A4988
//#define Z3_DRIVER_TYPE A4988
//#define Z4_DRIVER_TYPE A4988
#define E0_DRIVER_TYPE TMC2209
//#define E1_DRIVER_TYPE A4988
//#define E2_DRIVER_TYPE A4988
//#define E3_DRIVER_TYPE A4988
//#define E4_DRIVER_TYPE A4988
//#define E5_DRIVER_TYPE A4988
//#define E6_DRIVER_TYPE A4988
//#define E7_DRIVER_TYPE A4988


And to finish with the edition of the file “Configuration.h” we will edit two other very important parameters that we cannot forget. The first of them will help us to activate the Marlin emulation on our display.

This means that if you are using a “hybrid” display, you can change from TouchMode to marlin (text) mode by pressing the main button for 3 seconds. It is an incredible function, I personally hate touch screens and I have always preferred the original Marlin menu, so it goes to my hair as they say.

The second parameter will allow us to support eeprom storage on our printer, it is also essential to activate it.

// RepRapDiscount FULL GRAPHIC Smart Controller
* Persistent storage to preserve configurable settings across reboots.
*   M500 - Store settings to EEPROM.
*   M501 - Read settings from EEPROM. (i.e., Throw away unsaved changes)
*   M502 - Revert settings to "factory" defaults. (Follow with M500 to init the EEPROM.)
#define EEPROM_SETTINGS     // Persistent storage with M500 and M501



Modifying “Configuration_adv.h” file

It is the turn of the file “Configuration_adv.h”. If you have done your homework and read our previous article on how Configure Marlin 2.x from scratch, you will know that this file stores more advanced configurations on Marlin, as well as more experimental or in development ones.

The first parameter that we must modify is the interpolation of the steps of our driver. In this way, we will allow the TMC2209 driver to do it automatically.

#define INTERPOLATE       true  // Interpolate X/Y/Z_MICROSTEPS to 256


Then we will indicate the voltage and the micro steps to which each of the motors must operate. I only have X, Y, Z and E0, so I will modify the values ​​in the corresponding section. If you have an extra extruder or double Z axis, you must add it.

#define X_CURRENT       850        // (mA) RMS current. Multiply by 1.414 for peak current.
#define X_CURRENT_HOME  X_CURRENT  // (mA) RMS current for sensorless homing
#define X_MICROSTEPS     16    // 0..256
#define X_RSENSE          0.11
#define X_CHAIN_POS      -1    // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...

#define Y_CURRENT       850
#define Y_MICROSTEPS     16
#define Y_RSENSE          0.11
#define Y_CHAIN_POS      -1

#define Z_CURRENT       850
#define Z_MICROSTEPS     16
#define Z_RSENSE          0.11
#define Z_CHAIN_POS      -1

#define E0_CURRENT      600
#define E0_MICROSTEPS    16
#define E0_RSENSE         0.11
#define E0_CHAIN_POS     -1


Now we are going to indicate to Marlin what voltage our power supply offers us, and the most common is 12V or 24V. As in my case it is 24V, I indicate it to Marlin in the following way:

* Optimize spreadCycle chopper parameters by using predefined parameter sets
* or with the help of an example included in the library.
* Provided parameter sets are
* CHOPPER_PRUSAMK3_24V // Imported parameters from the official Prusa firmware for MK3 (24V)
* CHOPPER_MARLIN_119   // Old defaults from Marlin v1.1.9
* Define you own with
* { <off_time[1..15]>, <hysteresis_end[-3..12]>, hysteresis_start[1..8] }


We activate various temperature protections for our TMC2209 drivers that Trinamic offers us, among other things:

* Monitor Trinamic drivers for error conditions,
* like overtemperature and short to ground.
* In the case of overtemperature Marlin can decrease the driver current until error condition clears.
* Other detected conditions can be used to stop the current print.
* Relevant g-codes:
* M906 - Set or get motor current in milliamps using axis codes X, Y, Z, E. Report values if no axis codes given.
* M911 - Report stepper driver overtemperature pre-warn condition.
* M912 - Clear stepper driver overtemperature pre-warn condition flag.
* M122 - Report driver parameters (Requires TMC_DEBUG)


We proceed to activate the StallGuard ™ option in our Marlin firmware. StallGuard™ is a Trinamic patented technology that allows load measurements to be made on our stepper motors.

And you’re wondering, what the hell do I need that for? Well the answer is simple. StallGuard™ can accurately detect motor shutdowns and thus eliminate any type of endstop. If you are a maniac with cables, you will appreciate being able to remove all that extra wiring from your machine and leave everything cleaner.

I recommend removing only the X and Y axis limit switches, leaving a self-leveling sensor in Z. You should simply uncomment the option SENSORLESS_HOMING and it will be available.

You can also configure the sensitivity with the X_STALL_SENSITIVITY and Y_STALL_SENSITIVITY parameters. The value 0 means that it will not stop and the value 255 indicates that the slightest obstacle disables motor movement. A recommended value to start with is 100 , this is how I left it in my firmware.

#define SENSORLESS_HOMING // StallGuard capable drivers only

// TMC2209: 0...255. TMC2130: -64...63
//#define SPI_ENDSTOPS              // TMC2130 only


With this parameter we will have a more accurate signal for our drivers. It is recommended to activate it so we will do it as follows:

* Beta feature!
* Create a 50/50 square wave step pulse optimal for stepper drivers.


And finally, we will activate this option, which will give us the possibility to debug and know in real-time the status of our drivers. It is quite useful to know if we have configured everything correctly and if we have UART mode correctly activated.

* Enable M122 debugging command for TMC stepper drivers.
* M122 S0/1 will enable continuous reporting.
#define TMC_DEBUG


And well, so far everything is ready in the Marlin side. As you can see there have not been excessive changes, but now we must modify the “hardware” part of our drivers, and depending on the manufacturer it may vary a little. We explain it in the next section.


Configuring the hardware (SKR v1.4 and TMC Drivers)

After having left Marlin completely configured, we will proceed with the changes at the hardware level of our electronics (SKR board) and TMC drivers. In this way, we will make our electronics able to communicate intelligently (UART), and have each and every one of the advantages of working with TMC drivers.

I would like to take advantage of this point of the article to remind you that we also have in 3DWork a very interesting article on TMC drivers (Trinamic) where you can discover all the technologies they make available to you. You can access it by clicking on TMC Drivers: Guide to the best drivers and their 3D printing technologies.

As I have mentioned a few lines above, there are various manufacturers of TMC drivers. It has an easy explanation, the company Trinamic sells the microcontrollers (chips) to the manufacturers directly and they develop their own boards with the reference they have acquired. Actually, it should not matter in excess of which manufacturer is the driver that you have acquired, since all the functions are integrated in the chip that they assemble.

However, it is true that some manufacturers “make things easier”. I will expose here the different configurations for each manufacturer of TMC2209 drivers and in case I am missing any, do not hesitate to write me a comment at the end of the article and I will try to add it if I have access to the information. Or if you wish, through our social networks.


Drivers TMC2209 BIGTREETECH V1.1/V1.2


BigTreeTech, the company behind SKR electronics, also develops its own drivers that mount the TMC2209 chip. They are very easily distinguished since, as in the previous driver, the name and version are printed on the top of the plate.

If this is your case, configuring them for UART mode could not be easier. First of all, extract all the jumpers from your board and leave only those in the MS3 position in place, as you can see in the image below (click to enlarge).


With this simple modification should be enough to have a smart UART and StallGuard™ mode, and we will be able to use X and Y motors without limit switches.

According to the manufacturer’s documentation, if you only want the smart UART mode and you will continue to use mechanical limit switches for the X and Y motors, they recommend cutting a driver pin as you can see in the image below.

Since cutting to me personally seems like a bit of a drastic measure, you can choose to carefully fold it or blend to one side. This way if in the future you want to change the configuration and use them in Sensorless mode (without mechanical limit switches), you can do it without any problem.

TMC2209 Cutting Diagpin


Drivers TMC2209 FYSETC V3.0


The company FYSETC, famous for selling its own electronics, develops drivers with the TMC2209 chip that you can see in the image above, and which are the ones that I have installed on my 3D printer.

To put them in smart UART mode and use the StallGuard™ function (without limit switches), you only have to use two simple jumpers that I am going to show you in the following images.

First of all we are going to put a jumper in our SKR electronics in an unorthodox way with a diagonal jumper . It may seem strange, but in this way we will avoid adding unnecessary cables. Of course, try to do it with great care so as not to excessively damage the pins.

SKR Modification UART3

In the image above you can see how I did it. I have only removed the driver on the X motor so that it is exposed and you see exactly which pins are the ones that must be jumpered diagonally. Obviously you will have to do it in all those that you want to activate UART and StallGuard™ (Sensorless).

Then, and to finish, you must put another jumper directly on all the drivers. Specifically you need to bridge the RX and TX pins , as you can see in the image below (click to enlarge). And with this, we would already have everything configured.

FYSETC modification


Drivers TMC2209 MKS V1.0

TMC2209 MKS V1.0

The manufacturer of electronics and other 3D printing components Makerbase, also offers us in-house drivers. As usual, in our SKR electronics we will only have to jumper the MS3 line with a jumper in each of the motors that we want to activate UART and Sensorless.


Then in the drivers you will have to bend “by hand” the DIAG pin to match the DIAG connector on the SKR board . I leave you image below so you can see how it was in a user who made this modification.

Mod TMC2209 MKS V1.0

After put the drivers in our electronics, and verifying that it connects the DIAG lines of driver and board completely well, we will have UART + Sensorless available.


Drivers TMC2209 MKS V2.0

TMC2209 MKS V2.0

After the version of drivers TMC2209 MKS v1.0 it seems that Makerbase changed the position of the DIAG pin in its drivers v2.0. This important improvement results in not having to make any kind of modification to our TMC2209 MKS v2.0 drivers.


As you can see in the following image (click to enlarge), they changed the position of the DIAG of the vertex of the triangle to another position, which turns out to be the same as that of DIAG1 of our SKRs, a great success for users of these electronics.

So officially we can affirm that this is the driver that offers the easiest to mount on our SKR v1.4 electronics.

However, as always, we must activate the UART + Sensorless mode on our board, so we will follow the usual instructions, I leave the image below of the position of the jumpers.



Drivers TMC2209 WATTEROTT V2.0

Watterott TMC2209 modification3

Watterott is another manufacturer of TMC drivers, although in this case the modification may be a little more laborious, since we will need to carry out 5 operations (2 in our SKR v1.4 electronics and 3 in the driver) and a kind of “invention” that I will explain later.

In the image above you can see the modifications that must be made on the electronic board. A jumper that we will place in the MS3 position (indicated by the red lines) and then a jumper by soldering on the back of our electronics. We must do this with our soldering iron, tin and a little bit of skill (in the image in yellow).

Watterott TMC2209 modification

After having finished both modifications on the SKR v1.4 / v1.4 Turbo board, we will proceed to make the appropriate modifications to our drivers. In the image above you can see the 3 operations to perform (click to enlarge). In short, delete/cut a pin, solder an “extra” pin to our driver and finally a jumper in PDN/UART, as you can see.

Ok, we have the SKR board and the driver ready, now the last thing we should do is the following. The pin that you have soldered in the driver is the one that corresponds to the DIAG data line. In an ideal world, when we already click the driver on the board it should match, but in our electronics the DIAG pin does not match in the position that you soldered the pin on the driver.

DIAG ModIf you look at the first image that I put, I indicate in blue which is the DIAG1 pin in the SKR and it is in the third position (starting from the bottom). However, in the driver it is in the second position, so when you click it it will not be in the correct position.

So you are going to have to put a fairly long pin and make a couple of doubles, so that when you click it it fits into the hole next to it (and not the one that corresponds to it). I leave you here an image so that I can get you out of doubt (click to enlarge).

And well, with all this you should already have your TMC2209 Watterott drivers operating in UART mode and without any type of limit switch (Sensorless).


Drivers TMC2209 ERYONE V3.0


Finally, in this list of TMC2209 Drivers from the different manufacturers I know, we would find the driver belonging to the Eryone company. In principle I was not going to add it, since I do not have enough information about it except for a user who did seem to work UART mode without problem.

The first thing we should do is configure our SKR v1.4 electronics as we have been doing, placing a jumper on MS3.


Then as usual, you must connect the DIAG pin of the driver to DIAG1 of your SKR electronic board. Unfortunately in this case the pin does not match either, so you will have to deviate the pin again to fit the one on the board.

TMC2209 ERYONE3In this image (click to enlarge) you can see where the DIAG is in each of the two components (board and driver), and how to link it.

If you have one of these drivers and manage to locate DIAG and activate UART + Sensorless, do not hesitate to let me know, since I have no confirmation that it will be operational.


Verifying UART communication

Testing TMC2209 UART1

After having made every one of the necessary modifications, you must test whether UART is already working correctly. It is easy to make a mistake on a pin, especially if you have to do many modifications.

Also think that you have to do it in at least 3 or 4 motors, the odds as you can imagine of having made a mistake soar. So let’s check if the whole process went well.

There is a very simple way to determine if we already have UART smart communication. If you remember correctly, while configuring our Marlin firmware, we activate an option called MONITOR_DRIVER_STATUS.

This option offers us the possibility of using a series of very interesting GCodes to monitor the TMC2209 drivers. They are as follows:

  • M906Set or get motor current in milliamps using axis codes X, Y, Z, E
  • M911Report stepper driver overtemperature pre-warn condition
  • M912Clear stepper driver overtemperature pre-warn condition flag
  • M122Report driver parameters (Requires TMC_DEBUG)

The command that we are going to use will be the M122, in this way a series of parameters and values ​​established in our drivers will be sent to us on the screen, and thus we will verify that they are communicating via UART with our electronics correctly.

To send the M122 command I usually use Repetier. Not that it is better or worse than Pronterface (another alternative), but I used it for many years as a Slicer and I use it when I need to send some g-code command. You can also use the g-code emulator offered by the TFT35 hybrid display, but it shows so much information that it is not recommended.

In this image you can see the output of the M122 command on the Repetier log screen. It shows you a multitude of parameters and their assigned values, such as the configured voltage, the established micro steps, the StallGuard configuration and its Marlin values ​​and many other interesting things.

Testing TMC2209 UART2

All this would not be available if we had not established UART as a communication mode and connected the DIAG pin a of the driver to our SKR board.


Display TFT35 Bigtreetech V3.0 “Hibrid”

Display TFT35 V30

I have to confess that the “hybrid” BIGTHREETECH screens are truly spectacular. I have always preferred the Marlin menus on my MINI12864 Displays and have the possibility to activate / deactivate any firmware option without waiting for odious display updates that either arrive late or simply do not arrive. This is something that usually happens on TouchScreen displays.

I remember some time ago trying to activate the BabyStepping function with G-Code commands on TouchScreen displays and not being able to. And although it is hard to believe, that function exists since version 1.x.x of Marlin!.  Something vital to calibrate the prints on the first layer correctly.

When I first read that these displays emulated both modes, I was pleasantly impressed, so I decided to purchase one for myself SKR electronics without hesitation. What don’t you want to complicate yourself and you’re only going to print? You choose TouchScreen mode. What do you want all the power and versatility of Marlin? You switch to the Marlin emulator, it’s that simple.

And this does not mean in any way that the TouchScreen mode is not complete, vice versa. It has almost all the functions that Marlin offers and that you need to use every day. The support from the programmers is noteworthy.

Display TFT35 V30 2

Because we are going to use both modes, we will need to make 3 connections on our display board, which are the ones you can see in the image above (click to enlarge). The 2 typical serial 12864 connections, which are the EXP1 and EXP2 connectors. And then the TouchScreen connector that SKR will use to communicate with the display, marked as TFT in the image.

In the video below you can see how to switch between MARLIN modes (text mode) to TOUCHSCREEN mode (touch screen). As you can see, simply press the main button for 4 seconds and it will give us the option to change to the desired mode.

You will excuse me for the quality of the video, since I do not have the support yet designed and I had to hold it with my own hands, but I think the process is perfectly visible. And by the way, if you see it in its entirety you will be able to discover how to use the G-Codes emulator that comes with the TouchScreen mode.

I have precisely executed the M122 command and so you see on the screen how it is verified that the printer has the TMC2209 drivers configured in UART smart mode.


Some final recommendations

It is likely that after compiling the Marlin firmware and uploading it to your electronics, an Eeprom error may appear on your Touchscreen or the Marlin emulation screen. If this is the case, don’t worry as it is normal.

You must run these g-code commands one by one (don’t insert them at once) and the problem will be solved. The commands are M502, M500 and M501 in this same order. I leave you here the description of what each of them does.

  • M502 – Full reset to factory settings. It does not require the EEPROM_SETTINGS parameter.
  • M500 – Save all the current configuration to our EEPROM.
  • M501 – Loads the current values ​​from the EEPROM.

Another problem that usually appears when we use the Touchscreen mode is that it indicates that there is no communication with our printer. That is because we have different communication speeds selected in our Marlin Firmware and on our display.

If you have followed this manual to the letter you will remember that we set the communication to 250,000 baud in Marlin (#define BAUDRATE 250000). Now you must locate on the display where the communication is configured and indicate this same value.

Remember that you have to do this from the “Touch mode”, not from the Marlin emulation (text mode). To make your task easier, I put the route to follow:



And well, for now this is it, I hope this article has helped you. It has been a little more laborious than I expected, but I think it is very worth being able to have all this information in a single article for future references from our entire community (in which I include you).

If you have any doubts or queries, or find an errata in it, something that I do not rule out due to its length, join our community on any of the social networks.

I also want to thank our partner Juanjo from Telegram channel de 3DWork his invaluable collaboration in its development, since he has given me his unconditional help from the first minute.


If you wish, you can find other interesting articles in 3DWork at the following links: