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www.lairdtech.com
Laird Technologies
BTM510/511
Bluetooth
®
Multimedia Module
The second method is initiated by resetting the device and then ensuring that the text string
“AT+BT&BISM&<cr>” is sent (where <cr> is the carriage return character). There is special code which
looks out for this magic command and terminates the autoconnect cycle if it sees it and confirms to
the host of that fact by sending an “OK” response.
Response: <cr,lf>OK<cr,lf>
7. AT+BTR
{Delete Outgoing Peer Address}
This command is used to delete the peer address previously stored using AT+BTR<bd_addr>.
Response: <cr,lf>OK<cr,lf>
8 AT+BTR? {Read Outgoing Peer Address}
This command is used to display the peer address stored in non-volatile memory, used to put the device
in pure cable replacement mode.
Response: <cr,lf>12346789012
<cr,lf>OK<cr,lf>
If the location is empty the response is as follows.
Response: <cr,lf>00000000000
<cr,lf>OK<cr,lf>
Bluetooth Profiles
This section covers S-Registers and AT-Commands that are related to supported Bluetooth Profiles on BTM.
1. Profile Activation
In order to activate available profiles and advertise them to potential client devices, S-Register 102 is
used. Per default, only SPP is activated (value=1). Other supported profiles can be activated by setting
the appropriate Flag in S-Register 102. Once S-Register 102 has been written, the changed value needs
to be saved to non-volatile memory (“AT&W”) and subsequently a reset (“ATZ”) or power cycle is
required. Please note that “AT&W” saves the content of all S Registers to non-volatile memory.
2. SPP (Serial Port Profile)
The serial port profile (SPP) is used for serial data transmission with a remote device in both directions.
It behaves like a wireless replacement for a serial cable.
SSP belongs to the group of serial stream oriented profiles (SSO) so please refer to page 24 too.
In order to use SPP, the profile must be enabled in S102 (value=1). If it was not enabled earlier, set the
S register accordingly and issue AT&W followed by ATZ.
2.1 SPP Example
This section gives an example on how an SPP connection between two Laird Technologies
BTM devices can be established. It is assumed that two devices A and B are connected to a terminal
program, e.g., Ezurio Terminal on a PC. The example sequence of AT commands is listed in Table 3.9.
Figure 3.2 through to Figure 3.5 are presenting appropriate screenshots with Ezurio Terminal.
Phase
Dev.
AT Command
Comment
Preparation
A
AT&F*
Restore factory default settings
ATS102=1
Enable Serial Port Profile (SPP)
AT&W
Store settings
ATZ
Reset
Preparation
B
AT&F*
Restore factory default settings
ATS102=1
Enable Serial Port Profile (SPP)
ATS0=1
Automatic response after one “RING”
AT&W
Store settings
ATZ
Reset
AT+BTP
Make device temporary connectable and discoverable
ATI4
Query Bluetooth device address of local device <BdAddr_DevB>
AT COMMAND SET
REFERENCE
