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www.lairdtech.com
Laird Technologies
BTM520/521
Bluetooth
®
Multimedia Plus Module
CONFIGURING
THE BTM520/521
14. ATO {Enter Data Mode} (letter ‘o’)
Return to data mode. Assume that the module is in data mode after OK is received. Responds with
an error if there is no Bluetooth connection.
Response: <cr,lf> CONNECT 123456789012<cr,lf>
Or
Response: <cr,lf>ERROR nn<cr,lf>
15. AT&Fn {Set S Register Defaults}
This command will only work when the device is in local command and unconnected mode.
Depending on the value of ‘n’ it installs S Register values appropriate for various power modes,
ranging from minimum power consumption to maximum.
Legal values of ‘n’ are as per the following table. All other values of n will generate a syntax
error response. If ‘n’ is not specified then a default value of 0 is assumed where the baud rate
is NOT changed.
The new values are NOT updated in non-volatile memory until the AT&W command is sent to
the device.
Response: <cr,lf>OK<cr,lf>
Or
Response: <cr,lf>ERROR nn<cr,lf>
General Bluetooth Control
1. AT+BTAn {Control Audio Channel}
Once a Bluetooth connection is active, and assuming the peer device is also a Laird Technologies device,
this command is used to start/stop a SCO channel to transfer audio between the two peer devices.
On receipt of the command, the following response immediately follows.
Response: <cr,lf>OK<cr,lf>
The lower layers then go through the process of setting up the SCO channel, and as soon as
a SCO link is established, the following response is asynchronously sent to the host.
Response: <cr,lf>AUDIO ON<cr,lf>
Or if the SCO failed to be established.
Response: <cr,lf>AUDIO FAIL<cr,lf>
On the peer device, the host will asynchronously get ….
Response: <cr,lf>AUDIO ON<cr,lf>
&F0 (Default)
Medium power consumption, UART baud rate unchanged.
&F1
Minimum power consumption, UART baud rate set to 9600.
&F2
Minimum power consumption, UART baud rate set to 38400.
&F3
Minimum power consumption, UART baud rate set to 115200.
&F4
Medium power consumption, UART baud rate set to 115200.
&F5
Maximum power consumption, UART baud rate set to 115200.
&F6
Maximum power consumption, UART baud rate set to 115200.
+BTA0
Switch off the channel.
+BTA1
Switch on the channel.
