posted by bluelimn 2016.01.07 16:51

RFCOMM


frame types

  - SABM (Set Asynchronous Balanced Mode command)

    : connect with remote server channel

  - UA (Unnumbered Acknowledgement response)

    : response for SABM/DISC

  - DM (Disconnected Mode response)

    : when RFCOMM is disconnected

  - DISC (Disconnect command)

    : disconnect with remote device

  - UIH (Unnumbered information with header check command and response)

    : send and receive data with remote device.


SCN(Server Channel Number)

Server applications registering with an RFCOMM service interface are assigned a 

Server Channel number in the range 1…30. [0 and 31 should not be used since 

the corresponding DLCIs are reserved in TS 07.10] It is this value that should be 

registered in the Service Discovery Database.

  - MAP, PBAP, HFP can obtain SCN from  SDP.

  - SCN 0 means  control channel.


Supported Control Channel Commands

 - DLC parameter negotiation (PN)


DLCI (Data Link Connection Identifier) 

  - DLCI 0 : control 

  - DLCI even : initializing connection

  - DLCI odd : non-initializing connection


DISC (Disconnect command) 

The DISC command shall be used to terminate an operational or initialization mode previously set by a command. It

shall be used to inform one station that the other station is suspending operation and that the station should assume a

logically disconnected mode. Prior to actioning the command, the receiving station shall confirm the acceptance of the

DISC command by the transmission of a UA response.


UA (Unnumbered Acknowledgement) response

The UA response shall be used by the station to acknowledge the receipt and acceptance of SABM and DISC commands.


C/R (Command/Response)

The C/R (command/response) bit identifies the frame as either a command or a response.


P/F (Poll/Final)

The poll (P) bit set to 1 shall be used by a station to solicit (poll) a response or sequence of responses from the other station.

The final (F) bit set to 1 shall be used by a station to indicate the response frame transmitted as the result of a soliciting (poll) command.


'BlueTooth > 기본기' 카테고리의 다른 글

"블루투스의 혁신" 블루투스 메시 네트워크 표준 발표로 IoT 확산  (0) 2017.10.16
Mesh Profile  (0) 2017.10.16
Air packet에서 Bluetooth clock 확인  (0) 2017.09.08
baseband ack nack concept  (0) 2017.09.08
bluetooth timeout spec  (1) 2016.01.28
RFComm  (0) 2016.01.07
GPP(Generic PIM Profile)  (0) 2015.12.15
Paging and Inquiry  (0) 2015.11.26
AVDTP signaling/Media  (0) 2014.10.23
kitkat install 다시 시작  (9) 2014.07.19
BLE 4.1  (0) 2014.06.25