User's Manual

Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
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CONN-GUIDE-BT740_v0.2
5.3.37 List Trusted Device
Command:
AT+BTTn?
Response:
<cr,lf>12346789012
<cr,lf>12345678913
<cr,lf>12345678914
<cr,lf>OK<cr,lf>
Or
<cr,lf>ERROR nn<cr,lf>
Description:
This command lists the contents of either the ‘rolling’ or the ‘persist’ trusted device
database, where n=0 for the rolling database and 1 for the persist database. The link
key does NOT display so the response is as shown below. If the list is empty then just
the OK response sends; otherwise an OK terminates the list. Use the command ATI6
to read the maximum size of the trusted device database.
5.3.38 Transfer Device To ‘Persist’ List
Command:
AT+BTT<bd_addr>
Response:
<cr,lf>OK<cr,lf>
Or
<cr,lf>ERROR nn<cr,lf>
Description:
When a successful pairing occurs, the new link key automatically stores in the ‘rolling’
database where if the database is full, the oldest device is deleted. This poses a risk of
a trusted device automatically deleting, especially when the module is in ‘just works’
simple pairing mode and so pairings can occur without the host being involved and so
there is a definite risk of link key deletion.
This command transfers a device specified via the address supplied to the ‘persist’
database so that a trusted device is never deleted automatically.
5.3.39 Initiate a Pairing
Command:
AT+BTW<bd_addr>
Response:
<cr,lf>OK<cr,lf>
Or
<cr,lf>ERROR nn<cr,lf>
Description:
This initiates pairing with a device whose Bluetooth address is <bd_addr>. An OK
response sends immediately and when the PIN or PASSCODE is required.
Asynchronous indications send to the host in the form PIN? <bd_addr> or PASSKEY?
<bd_addr> or PAIR ? <bd_addr> where the address confirms the device with which the
pairing is to be performed. To supply a PIN or passcode, use the AT+BTK command.
To respond with a YES or NO, use the command AT+BTKY or AT+BTKN respectively.
For a successful pairing, the link key automatically stores in the ‘rolling’ database which
can be queried using the AT+BTT0? Command.
Note: The “OK” response sends immediately on receipt of the AT+BTW command. On
pairing completion, an unsolicited message sends to the host in the form PAIR n
<bd_addr>, where n is 0 for a successful pairing.