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 This variant can be used to control the board from another board(e.g. Arduino, ESP32, ESP8266,RASPBERRY PI) or a computer via a serial protocol.<br />
 The example [Arduino sketch](https://github.com/EmanuelFeru/hoverboard-firmware-hack-FOC/blob/master/Arduino/hoverserial/hoverserial.ino) will send commands and process the feedback.<br />
+Voltage [Control Mode](https://github.com/EFeru/hoverboard-firmware-hack-FOC#foc-firmware) is used by default for this variant.
 
 You can also test this variant with following [Web Tool](https://github.com/Candas1/Hoverboard-Web-Serial-Control), it let's you control the board and trace feedback values.<br>
 This [Python code](https://github.com/kosni68/HoverSerial) inspired by the code shared in this [issue](https://github.com/EmanuelFeru/hoverboard-firmware-hack-FOC/issues/157) can also be used to control the firmware.