How to connect a Fly-E3-Pro via WiFi


The Fly-E3-Pro is an STM32F407VGT6 based board.

Downloading the board firmware

Choose the firmware (firmware-stm32f4-wifi.bin) from here. You can choose to download either the latest release (marked latest and classed by us as stable) or the latest pre-release if available (marked pre-release and classed by us as unstable).

Once downloaded, rename it firmware.bin

WiFi firmware preparation

Choose the correct corresponding firmware from here.

  • DuetWiFiServer-32-X.XX-XX.bin

Once downloaded, rename it DuetWifiServer.bin

DWC (DuetWebControl)

The correct version of DWC should be downloaded from here.
The version you download should be of the same version number as the board firmware you downloaded above.
For example, if version 3.4.0 of the board firmware has been downloaded, 3.4.0 of DWC should be downloaded.

Generate a config

We provide a handy online tool to assist you in generating a set of config files for your 3D printer. The configurator doesn’t cover all options that RRF can be used for (such as dual motor axis control, which can be manually added later), however it does give a good start.

We also have a collection of user created configs which can be a useful reference. They can be found here

Manual board.txt Changes

If you are using a set of config files provided by someone else or have no need to use the configurator, you will need to create your board.txt file manually.

Below are the contents that should be used.

//Config for Fly-E3-Pro
board = fly_e3_pro
//WiFi pins
8266wifi.espDataReadyPin = PE_13
8266wifi.TfrReadyPin = PE_14
8266wifi.espResetPin = PE_15

// RX/TX Settings
8266wifi.serialRxTxPins = { PD_9, PD_8 }

heat.tempSensePins = { PA_3, PA_4, PA_1 }

stepper.numSmartDrivers = 5

If the WiFi adapter is not working correctly e.g. error: “Failed to attach interrupt to pin G.10” after restarting the module (M552 S-1; M552 S0) check that the interrupt is not already used e.g. with “e1stop”. See also here.

SD Card preparation

Now all the required files have been gathered, the SD card structure needs to be created.

SD Card Specification

When choosing an SD Card to use with RRF, we recommend one with the following features:

  • a branded card with a speed rating of Class 4 or higher
  • of up to 32GB capacity, formatted as below. RepRapFirmware does not support SD cards formatted in exFAT format.


If you can’t use the recommended formatting tool, then the following points should be taken into account:

If you need to reformat the micro SDHC card:

  • If the capacity of the card is 4GB or lower, use FAT16 format
  • If the capacity is more than 4GB (up to 32GB) then you will have to use FAT32 format
  • All cards should be formatted with 512 byte sectors
  • For best upload speed choose the largest cluster size available, which is normally 64kb for FAT16 and 32kb for FAT32

SD Card Structure

The following structure should be replicated on your SD card.

sd card root/
├─ filaments/
├─ firmware/
│  ├─ DuetWifiServer.bin
├─ gcodes/
├─ macros/
├─ sys/
│  ├─ bed.g
│  ├─ board.txt
│  ├─ config.g
│  ├─ homeall.g
│  ├─ homex.g
│  ├─ homey.g
│  ├─ homez.g
│  ├─ pause.g
│  ├─ resume.g
│  ├─ sleep.g
│  ├─ stop.g
│  ├─ tfree0.g
│  ├─ tpost0.g
│  ├─ tpre0.g
├─ www/
│  ├─ contents of

In the above example, the contents of the sys folder have come from the online configurator.

The contents of should be extracted into the www folder.

Final Setup

Once connected, power up the board using 12-24v and connect to the USB port on the board. Connect to the board using a program such as putty. Follow the instructions here to set it up for RRF. Change the Com port to match the Fly-E3-Pro and connect. The baudrate doesn’t matter.

Flashing the WiFi Firmware

Type in the following to putty

M552 S0
M997 S1

Wait for the uploading of the WiFi firmware to finish.

Sending your WiFi Credentials

Send the following

M552 S0
M587 S"your SSID" P"your password"
M552 S1

The blue light on the WiFi chip shoould then flash blue and will go solid when a connection has been established. The ip address will be shown on the serial connection. It is also possible to type just M552 to get the current ip address reported back.

The final thing to do is add the line “M552 S1” to your config file. This can be done through the web interface. This just ensures that the WiFi connection is started at start up. There is no need to add the M587 command as this is written permanently to the flash of the ESP8266 chip.

Once up and running

You will need to PID tune your tools and your bed. Please be aware that bed tuning may take up to an hour and tool tuning normally takes around 15 minutes. If it takes longer, that is also fine as up to 30 cycles may be ran.

To tune the bed, run the following command, changing the temperature (the S value) if a different tuning temperature is required.

M303 H0 S60

To tune each tool, run the following command, changing the temperature (the S value) if a different tuning temperature is required. This proceedure will activate the part cooling fans during the final phase of the tuning process so their effect is taken into account. If your printer has more than one tool, make sure each one of them is tuned.

M303 T0 S220

Once the tuning is complete, either copy the M307 command into the heater definitions or send M500, ensuring you have M501 at the end of your config.g.
If the tuning fails at the end, carry on saving the values as in most cases the outputted values still work correctly.
If the values still result in a heater fault, please refer to this wiki page for information about how to adjust the values manually.