QCC3040----GAIA protocol协议解析

 

This is the protocol used for all vendor specific commands. Fields longer than 1 octet is sent in big endian order.

A packet consists of:
```
  0 bytes  1        2        3        4        5        6        7        8      len+8      len+9
  +--------+--------+--------+--------+--------+--------+--------+--------+ +--------+--/ /---+ +--------+
  |  SOF   |VERSION | FLAGS  | LENGTH |    VENDOR ID    |   COMMAND ID    | | PAYLOAD   ...   | | CHECK  |
  +--------+--------+--------+--------+--------+--------+--------+--------+ +--------+--/ /---+ +--------+
```

| Field         | Length (bytes) | Description |
|---------------|----------------| -------------|
| SOF           | 1              | Start of frame, one octet with the fixed value 0xff. |
| Version       | 1              | This field indicates the protocol version in use. |
| Flags         | 1              | Bits within this field control protocol options: Bit[0]: If set, a single octet check is present. Bit[1:7]: Reserved, must be 0. |
| Length        | 1              | Number of payload bytes. |
| Vendor ID     | 2              | Vendor ID. |
| Command ID    | 2              | Command ID. In command responses, the highest bit (0x8000) is set. |
| Payload       | Length         | The payload contains any information that a specific command must pass. It consists of zero or more octets depending on the command. |
| Check         | 1              | If present, this field is determined by XORing together the other octets in the packet. |