PixelHub/PixelHub Protocol.md

PixelHub Protocol Documentation

Version 0.1

The PixelHub Protocol is a communication protocol for WiFi-capable Hull PixelBots to communicate with and be controlled by a remote server. While the protocol is binary, it is designed to be fairly easy to parse and implement.

Basic Information

The PixelHub Protocol is conducted over a single TCP connection. Obtaining these details can be done automatically by listening to the UDP multicast beacon set up by the server.

In this specification document, when referring to bytes, The C++ notation will be used. Examples: 0b00000000, 0b01010101.

Each PixelHub message is terminated by a null byte (0b00000000).

Conversation Flow

• [ Hub -> Bot ]: Send instruction
• [ Bot -> Hub ]: Acknowledge instruction
• [ Bot ]: Execute command
• [ Bot -> Hub ]: Notify about instruction completion

Message Struture

Basic Message

+--------+--------+--------+--------+
| Byte 1 | Byte 2 | Byte 3 | Byte 4 |
+--------+--------+--------+--------+
| Message Type    | 
+--------+--------+--------+--------+
| Message Id                        |
+--------+--------+--------+--------+
| Message Contents                  |
+--------+--------+--------+--------+
| Null   |
| Byte   |
+--------+