Note: The causes of ERR can be introduced by syntax error of AT Command or non-applicable
operating state for the incoming command.
2.3 Report
If the incoming AT command requests certain information from a20-RX-ATC. It will provide the
requested results in the Report that sent to host.
The syntax of Report begins with the key word ‘REP:’ and then followed by the processing results
that correspond to the AT command. The contents of each type of Report will be described with
corresponding AT Command in the following sections.
REP: Profile Identifier Command Character Parameter
(optional) \r
(0x0D) \n
(0x0A)
2.4 Event
Event occurred at any timing during the communication such as Pairing successfully, connected,
disconnected,…..and so on. These are usually asynchronous to the transaction of AT Commands.
Therefore, it is usually initiated by a20-RX-ATC to notify the host about situation of existing Bluetooth
link.
The syntax of Event begins with the key word ‘IND:’ and then followed by the related messages from
a20-RX-ATC.
IND: Profile Identifier Attribute Character Parameter
(optional) \r
(0x0D) \n
(0x0A)
Contents:
3. System Control Command Set:............................................................................................................. 5
3.1 Enter Pairing mode....................................................................................................................................5
3.3 Reply The Pin Code...................................................................................................................................6
3.4 Connect to Remote Device........................................................................................................................6
3.5 To Drop Bluetooth Connection ..................................................................................................................7
3.6 Set PIO for Output .....................................................................................................................................7
3.7 Read Input Value from PIO........................................................................................................................8
3.8 Baud Rate Control .....................................................................................................................................8
3.9 Set Stop bit ................................................................................................................................................8
3.10 Set Parity bit.............................................................................................................................................9
3.11 Deep Sleep Mode....................................................................................................................................9
3.12 Get Current Bluetooth State.....................................................................................................................9
3.13 Bluetooth Link Dropped Indication........................................................................................................ 10
3.14 Get the local BD address...................................................................................................................... 10
3.15 To Enable/Disable Local Echo.............................................................................................................. 10
3.16 To Set The Local Name........................................................................................................................ 11
3.17 Inquiring Firmware Version Number..................................................................................................... 11
3.18 DFU operation....................................................................................................................................... 11
3.19 Reset and Factory Settings................................................................................................................... 12
4. A2DP Command Set:.......................................................................................................................... 13
4.1 Volume Control....................................................................................................................................... 13
4.2 Get Current Audio Volume...................................................................................................................... 13
4.3 Get Current A2DP State ......................................................................................................................... 13
4.4 Playback Control..................................................................................................................................... 14
4.5 Mute Indication........................................................................................................................................ 14
4.6 Media Attribution Indication..................................................................................................................... 14
4.7 Media Codec Indication .......................................................................................................................... 15
4.8 A2DP Sampling Rate Indication ............................................................................................................. 15
5. HFP/HSP Command Set:.................................................................................................................... 16
5.1 Answer Incoming Call............................................................................................................................. 16
5.2 Reject Incoming Call............................................................................................................................... 16
5.3 Hang Up Call........................................................................................................................................... 17
