Data Pass-through Channel Service

Last Updated on : 2024-06-24 08:13:32download

Integration of standard Bluetooth Low Energy (LE) protocol provides data pass-through channel services for MCU and mobile app under Bluetooth LE connection. Thus, meet customized requirements and implement direct communication between the two parties.

Overview

Thanks to the generic Bluetooth module, the data pass-through channel service enables the MCU to directly establish a communication channel with the mobile app over Bluetooth, helping meet the varied development needs of the MCU.

Scenarios:

Complex protocol interaction scenarios where direct communication with the mobile app or panel is required.
Scenarios that require coordination with custom panel logic.
Certain services that are specific to a line of business.

Applicable firmware: Currently, only BF6H Bluetooth LE generic firmware supports this service, and other firmware will be available soon.

Related protocols

Enable/disable data pass-through channel (0xC400)

This channel is disabled by default. When a product needs to use this channel, you can run the command to enable it. This channel supports transparent transmission of data reporting and sending. The module does not process specific data, but directly transmits the raw data to the app for processing.
An error will be returned if the data pass-through channel is used before it is enabled.

MCU -> module:

Field	Bytes	Description
Header	2	0x55 0xAA
Version number	1	0x00
Command (CMD)	1	0xC4
Data length (Len)	2	0x02
Subcommand	1	0x00
DATA	1	`0x00`: Disable `0x01`: Enable
CRC8	1	Start from the header, add up all the bytes, and then divide the sum by 256 to get the remainder.

Module -> MCU:

Field	Bytes	Description
Header	2	0x55 0xAA
Version number	1	0x00
Command (CMD)	1	0xC4
Data length (Len)	2	0x02
Subcommand	1	0x00
DATA	1	`0x00`: Success `0x01`: Failure `0x02`: Length error `0x03`: Feature disabled
CRC8	1	Start from the header, add up all the bytes, and then divide the sum by 256 to get the remainder.

Transmit data through the pass-through channel (0xC401)

This channel supports two-way data transparent transmission. The module does not process specific data, but directly transmits the raw data to the app for processing. Typically, this channel is used in conjunction with custom logic in a panel or app.

MCU <-> module:

Field	Bytes	Description
Header	2	0x55 0xAA
Version number	1	0x00
Command (CMD)	1	0xC4
Data length (Len)	2	Upper 8 bits Lower 8 bits
Subcommand	1	0x01
DATA	Len-1	`RAW_DATA`: The raw data.
CRC8	1	Start from the header, add up all the bytes, and then divide the sum by 256 to get the remainder.

Example

Here are some examples of implementation through the data pass-through channel service.

Message notification

When the mobile phone receives a message notification, the module will send the following data in the specified format through the data pass-through channel.

Data format of message notification (data is sent through the data pass-through channel)
Field name	TYPE	DATA_LENGTH	DATA
Field length	1 byte	2 bytes	n byte(s)
Field value	…	n	…
The message notification is represented in type-length-data (TLD) format. The specific fields are as follows: TYPE: The notification type. DATA_LENGTH: The length of notification content, in big-endian format. DATA: The notification content.

Type, upper four bits	Sub-type, lower four bits	Values of type	Notification type	DATA_LENGTH	DATA
0000 Message notification-originally defined	0001	0x01	Phone call	…	The type with 1 byte. 0x01: incoming call 0x02: answer 0x03: hang up	Phone number (Unicode encoding) This field is available only when the type is incoming call.
	0010	0x02	SMS message	…	Unicode encoding: uses 2 bytes for 1 character. For example, the Unicode code of the Chinese character 今 is \u4eca, and the transmission sequence is 0xCA, 0x4E.
	0011	0x03	Tencent QQ	…
	0100	0x04	WeChat	…
	0101	0x05	Facebook	…
	0110	0x06	Messenger	…
	0111	0x07	Twitter	…
	1000	0x08	WhatsApp	…
	1001	0x09	Instagram	…
	1010	0x0A	LinkedIn	…
	1011	0x0B	Viber	…
	1100	0x0C	LINE	…
	1101	0x0D	Skype	…
	1110	0x0E	Outlook	…
	1111	0x0F	Others	…
0011 Message notification-new	0001	0x31	WhatsApp Business	…	Unicode encoding: uses 2 bytes for 1 character. For example, the Unicode code of the Chinese character 今 is \u4eca, and the transmission sequence is 0xCA, 0x4E.
	0010	0x32	Email	…
	0011	0x33	Calendar	…
	0100	0x34	KakaoTalk	…
	0101	0x35	VKontakte	…
	0110	0x36	Tumblr	…
	0111	0x37	Snapchat	…
	1000	0x38	Telegram	…
	1001	0x39	YouTube	…
	1010	0x3A	Pinterest	…
	1011	0x3B	TikTok	…
	1100	0x3C	Gmail	…
	1101	0x3D	Tuya	…

Example of message notification:

WeChat: It’s really hot today

55 AA 00 C4 00 0C 01 04 00 08 CA 4E 29 59 1F 77 ED 70 68
Hang up calls (03 indicates hang up):

55 AA 00 C4 00 05 01 01 00 01 03 CE
Incoming call (01 indicates incoming call): 15000000000

55 AA 00 C4 00 19 01 01 00 17 01 31 00 35 00 30 00 30 00 30 00 30 00 30 00 30 00 30 00 30 00 30 00 0C

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