CI230X - Serial Port Transmission Protocol Between Voice Terminal And WIFI Terminal¶

1. Overview¶

In order to reduce the coupling between the voice end and the WIFI end and increase the stability of the chip, two independent freeRTOS systems are running inside the CI230X chip; The voice end and WIFI end communicate through the serial port, and the communication rate can be set to 9600bits/s~2Mbits/s as required; The CI2306 chip uses the off line scheme. When transmitting audio data to the cloud, the serial communication rate is set to at least 921600bits/s.

The data structure, communication protocol and communication instructions of voice terminal and WIFI terminal communication will be introduced in detail below; If the user uses a third-party WIFI chip to cooperate with the Chipintelli CI130X voice chip, this agreement is also applicable.

2. Transmission of interactive data - data structure:¶

typedef struct
{
    unsigned int magic; /*  Start data frame.  Let's define as 0x5a5aa5a5; */
    unsigned short checksum; /*  checksum */
    unsigned short type; /*  Define command type. */
    unsigned short len; /*  Define data stream len. */
    unsigned short version; /* Version information*/
    unsigned int fill_ data; /* Fill Data*/
}cias_ standard_ head_ t;

3. Transmission of interactive data - data field analysis:¶

Name	Byte length	Meaning
Magic	4	Default protocol header, unsigned int type, default “5a5aa5a5”
Checksum	2	Checksum, unsigned short type, default “0000”
Type	2	Type of the current message, unsigned short type
len	2	The data length in the current message (excluding the length of the structure itself, it only represents the data length)
Version	2	version “Version information, default is” 00 “
fill_ Data	4	Fill in the data. The default “0x12345678” means the following
		If there is other data, it will follow the structure directly, eg memcpy (output+sizeof (cias_data_standard_head_t), (uint8 *) input, len)< Br/>(Note that users should manage the memory of output by themselves)

#define INVAILD_ SPEAK                (0x12345666)
#define RECV_ TTS_ PLAY                (0x12345677)
#define RECV_ MP3_ PLAY                (0x12345688)
#define RECV_ M4A_ PLAY                (0x123456aa)
#define IDLE_ STATUS_ RECV_ M4A_ PLAY    (0x123456ab)
#define RECV_ WAV_ PLAY                (0x123456bb)
#define DEF_ FILL                     (0x12345678)
#define WAKEUP_ FILL_ DATA             (0x12345678)
#define NO_ WAKEUP_ FILL_ DATA          (0x0)

4. Example: The voice terminal transmits a packet of PCM data to the WIFI terminal¶

4.1 Application layer sending:¶

voice_ data_ packet_ and_ send(SEND_PCM_MIDDLE, dst_addr, encode_t);

4.2 Bottom packaging:¶

broadlink_ frame_ create(packet_type, voice_data, packet_len,
(broad_link_buf + buff_count * 1024),1024,0x12345678,0);

4.3 Add to send queue:¶

send_ msg_ to_ network_ task(&send_msg,NULL)

4.4 Serial port sending:¶

network_ send((int8_t *)data->payload,data->length)

5. Serial port interaction instruction between voice terminal and WIFI terminal¶

The serial port communication command of voice end and wifi end is used internally in the system from 0x0101 to 0x0fff. If the user needs to add a command, please add a value outside the range, otherwise there will be a conflict, leading to communication exceptions.

Voice terminal instruction definition source file

SDK/projects/cias_ aiot_ audio/cias_ msg_ handle/cias_ network_ msg_ protocol.h

Wifi side instruction definition source file:

SDK/project/ci230x-wifi-sdk-combo/app/cias_ aiot_ wifi/cias_ msg_ handle/cias_ slave_ message_ handle.h

Instruction Type	Instruction Value	Instruction Description
Speech recognition command	0x0101	Local speech recognition notification
	0x0102	Wake up
	0x0103	Cloud VAD END
	0x0104	Skip invalid voice
	0x0105	PCM data tundish
	0x0106	PCM data end packet
	0x0107	PCM data idle
	0x0108~0x01ff	Reserved

Network play command	0x0201	Start playing
	0x0202	Pause playback
	0x0203	Resume playback
	0x0204	Stop playing
	0x0205	Replay
	0x0206	Play the next song
	0x0207	Play local TTS
	0x0208	End of playback
	0x0209	Retrieve the playback link
	0x020a	Get subsequent playback data
	0x020b	Receive playback data
	0x020c	Playback data received
	0x020d	End of playing tts
	0x020e	Play empty command
	0x020f~0x02ff	Reserved

IOT custom protocol	0x0301	Cloud IOT instruction
	0x0302	Cloud Volume
	0x0303	Local volume
	0x0304	Increase the volume
	0x0305	Decrease the volume
	0x0306	Maximum volume
	0x0307	Minimum volume
	0x0308~0x03ff	Reserved

Network configuration command	0x0401	Enter the distribution network mode
	0x0402	Distribution in progress
	0x0403	Exit the distribution network mode
	0x0404	Initial password status
	0x0405	Network disconnected
	0x0406	Network connection succeeded
	0x0407	Authentication file obtained
	0x0408	Authentication file needs to be configured
	0x0409	Cloud connected
	0x040a	The cloud is disconnected
	0x040a~0x04ff	Reserved

OTA related instructions	0x0501	Start ota
	0x0502	ota data
	0x0503	The ota upgrade is successful
	0x0504	Production test
	0x0505	Production test succeeded
	0x0506	Production test failed
	0x0507	Self test
	0x0508	Infrared data transmission
	0x0509	Infrared code library downloading
	0x050a	Infrared code library download completed
	0x050b	Start of infrared download code base
	0x050c~0x05ff	Reserved

	0x0601~0x0fff	Reserved