WARNING: Unlike updating the myCNC software, the firmware CANNOT be downgraded after a reflash. The myCNC team recommends reflashing the control board firmware as a last resort only, and recommends seeking an explicit confirmation from the support team that the firmware reflash is warranted in order to avoid issues.

NOTE: Make sure to select the firmware for the correct version/revision of your board! Firmware for ET7 boards (R1-R3) and ET7 boards (R4-R6, also known as the ET9) are DIFFERENT. Flashing incorrect version of the firmware will result in a non-functional board. If you're unsure of your board version, please contact myCNC Technical Support prior to the reflash:


myCNC-ET7 reflashing procedure may take up to 3 minutes.

To reflash the board:

1. Plug in the 24V DC power supply

2. Plug in the micro-USB cable into the ET7 controller & a Host Computer with myCNC installed. NOTE: The micro-USB cable must be capable of data transfer (not a simple micro-USB charging cable)

3. Close jumpers J5(reset) & J6(programming) on the controller board

4. Open (remove) the J5 jumper.

5. Open myCNC software on Host computer (Settings > Support Tab)

6. “Select board” set to “myCNC-ET7”

7. Select “Firmware version” from “Release”, “Night build” or “Testing” (“Release” is recommended)

8. “UART port” select port with FT232 attached

9. Baud Rate set to “115200” for ET7; other baudrate can be selected in case of problems on 115200 speed

10. Press “Update Firmware” button, Firmware download and reflashing process will be started

11. If “Sector 0; +” message is shown in the debug window, the reflashing process has finished successfully.

12. Remove all jumpers (J5, J6) and restart the board.

If the reflashing process failed, please check your internet connection and the micro-USB connection, and then repeat the reflashing procedure from Step 3.