LEGO Mindstorms EV3


This paragraph will document the communication protocol that is supposed to be used across the different communication platforms.

General Protocol Overview

  |Byte 0|Byte 1|Byte 2|Byte 3|      |      |      |Byte n|

  Byte 0 – 1: Command size, Little Endian\n

  Byte 2 – 3: Message counter, Little Endian\n

  Byte 4:     Command type. The 7 lowest bit of this byte is used for identifying the command type.
              Bit 7 (MSB) is used for identifying whether the command should give a reply message or not.

  Byte 5 - n: Dependent on command type


There are two different command types:

System commands are thought of as commands used to controlling/utilizing some of the more overall system functionalities (File download,...)

Direct commands are related to functionality which are controlled within by the virtual machine.

LEGO® Robotics Firmware Documentation
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