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Laird Technologies
BTM510/511
Bluetooth
®
Multimedia Module
2.2 ATA {Accept Incoming SPP Connection Request}
Accept an incoming connection, which is indicated by the unsolicited string <cr,lf>RING
123456789012<cr,lf> every second. 123456789012 is the Bluetooth address of the
connecting device.
Response: <cr,lf>CONNECT 123456789012,1101,<<cr,lf>
2.3 AT+SPD<bd_addr>
{Make Outgoing SPP Connection}
Initiate an SPP connection to device with Bluetooth address <bd_addr> and SPP profile.
The timeout is specified by S register 505.
For backward compatibility, the following command fulfils the same purpose: ATD<bd_addr>.
Response: <cr,lf>CONNECT 123456789012,1101,><cr,lf>
Or <cr,lf>NO CARRIER<cr,lf>
Due to a known issue in the Bluetooth RFCOMM stack, it is not possible to make more than
65525 outgoing connections in a single power up session. Therefore if that number is exceeded,
then the connection attempt will fail with the following response:
Response: <cr,lf>CALL LIMIT
Or <cr,lf>NO CARRIER<cr,lf>
In that case, issuing an ATZ to reset the device will reset the count to 0 and more connections
are possible.
Figure 3.4: SPP example Device A - initiate connection, receiving data, command mode, disconnect
Figure 3.5: SPP example Device B - incoming connection, receiving data, disconnection
AT COMMAND SET
REFERENCE