First steps with a Duet 2 Wifi

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Duet 2 Wifi
I have been testing a Duet 2 Wifi board lately. It is the first 3D printer / CNC controller board that I use that has a decent wireless upload speed. It is a well-thought-out board designed by David Crocker and Tony Lock, that features both an ARM ATSAM4E8E and ESP8266 module. The former handles the RepRapFirmware and the latter provides wireless connectivity to the mix. 

The board features five silent stepper motor drivers and heaters and fan controllers to be used on 3D printers or CNC machines. The built-in socket for an SD card allows its usage not only to hold the firmware and website files but also user folders containing g-code files that can be uploaded and managed remotely through the built-in web server. 

The only main problem for the newbie is SD card and board initialization, which should have been taken care of by the seller unless they are lousy. But the board I got did have an empty SD and no manual so I had to go Duet3.com site to get some answers in their Documentation pages. I am not sure where this board is coming from, as it was provided by a local company and as the design is licensed CERN OSH V1.2 I guess third parties besides the designer and manufacturer can be producing compatible boards too. A quick check on Aliexpress shows a bunch of models listed (which I do not know if they honor the license or not). 

So initialization is a bit of work if you have not done it before. There is a tool that should ease the configuration process. Details about your system's mechanism, motor axis, heaters and fans, speeds, and acceleration are provided through a series of menus and you get a set of configuration files at the end you can populate the SD card.

On top of that, you will need to add the firmware binary file (first link on the image above) and the Duet Web Control (second link on the image above) that contains all the needed files for the web interface. All of them need to go to the SD card too. 

And now that you have your card configured you are not yet there. Connect the board (with the SD card inserted) to the USB port and look for the new serial port that will add to your computer. It changes from one computer to another. I used the Arduino IDE that will notice the new serial port created and I will use the Serial Terminal to access the board.


The board will print several messages, not all of them at the same time. In the picture above you can see that it actually connected to a wireless network and it obtained an IP address, but this is not going to happen the first time as you still need to configure your Wifi network credentials. You can do that by sending the M587 command. For example as follows:  M587 S"your-wifi-name" P"your-wifi-password"

That will tell the board to try to connect to your network. If successful, you will see the blue led on the ESP8266 board to at first flash, and finally end up lit solid. If that does not happen at all, it might be because your wifi is not enabled. You can enable it using command M552 S1. 

Of course, you may learn more about any possible command in the firmware documentation. 

Once you have got the board connected to your home/office wifi network, a message stating its IP address will be shouted through the serial monitor. You can use now a browser on any computer or cellphone connected to the same network and point it to that address. The Duet Web Control will appear on your browser and you will be able to have full control of your board using it. The USB connection is no longer necessary (unless the board does not have any other power source). 


This is one of the pages of the web interface that allows you to start a new job, by uploading a new g-code file, stop the current one (if any) and perform manual moves on the different axis while you can monitor hotend temperature and machine axis location in real-time too.


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