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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 />
 Those commands are send as binary frames with following structure:<br />
-- Start frame : 0XABCD as unsigned int16
+- Start frame : 0xABCD as unsigned int16
 - Steer : -1000 to 1000 as signed int16
 - Speed : -1000 to 1000 as signed int16
 - Checksum : XOR checksum as unsigned int16