# Heliox communication protocol

> **Note:** 
>
> look into state-of-the-art protocols -> https://www.reddit.com/r/embedded/comments/11bxeux/whats_everyone_is_using_for_framing_and/
>- CBOR
>- MessagePack
>- Protobufs

The following structure can be used to communicate with the Heliox control over several carrier protocols (UART, BL LE,...)

## Basic data structure

The following table describes the bit pattern for a successful communication with and between Heliox devices.

| 0x0 | 0x1 | 0x2      | 0x3    | 0x4       | ...             |
| --- | --- | -------- | ------ | --------- | --------------- |
| H   | X   | _length_ | _mode_ | _submode_ | _optional data_ |

## Modes

### Mode selection

The columns represent modes and the rows represent submodes:

|       |     0x0     |        0x1        |        0x2        |             0x3             |
| :---: | :---------: | :---------------: | :---------------: | :-------------------------: |
|       | **Message** |   **Settings**    | **Light control** |     **Basic commands**      |
|  0x0  | light data  |   set baud rate   |        on         |     request light data      |
|  0x1  |    info     | set WIFI password |        off        | enter console flashing mode |
|  0x2  |   warning   |   set WIFI SSID   |      toggle       | exit console flashing mode  |
|  0x3  |    error    |                   |     increase      |       pair Bluetooth        |
|  0x4  |   success   |                   |     decrease      |            help             |
|  0x5  |             |                   |                   |           version           |
|  0x6  |             |                   |                   |            reset            |

### Optional data (out of date)

Every submode can take any number of Bytes except the below-mentioned ones:

|  **0 Bytes**   | **1 Byte** |
| :------------: | :--------: |
|       on       |  increase  |
|      off       |  decrease  |
| flash console  |   toggle   |
| pair Bluetooth |            |

### Additional information

The maximum length of a message ist 255 Bytes excluding the magic number "HX" and the length slot itself.