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www.lairdtech.com
Laird Technologies
BTM520/521
Bluetooth
®
Multimedia Plus Module
CONFIGURING
THE BTM520/521
REGISTER
DEFAULT
RANGE
COMMENT
S592
0
0..1
Set this to 1 to reduce the trusted device database to just 1 record
when autosaving of pairing is enabled via S reg 538
S593
0
0..1
Automatically append last 6 digits of local bluetooth address to the
friendlyname which was set via AT+BTN or AT+BTF
S689
0
-450..+215
Set codec output gain in dBr * 10
(applies to sink), default = 0
S690
0
-450..+215
Set codec input gain in dBr * 10
(applies to source), default = 0
S730
0
0..1
Enable Auxiliary DAC
S731
0
0..225
Set Auxiliary DAC Level
9. ATSn? {Read S Register Value}
This will return the current value of register n.
For recognised values of n
Response: <cr,lf>As Appropriate<cr,lf>OK<cr,lf>
For unrecognised values of n
Response: <cr,lf>ERROR nn<cr,lf>
10. ATSn=? {Read S Register – Valid Range}
This will return the valid range of values for register n.
For recognised values of n
Response: <cr,lf>Sn:(nnnn..mmmm)<cr,lf>OK<cr,lf>
For unrecognised values of n
Response: <cr,lf>ERROR nn<cr,lf>
11. ATZ<n> {Hardware Reset and emerge into mode ‘n’}
Forces the device through a hardware reset which means it will eventually come alive in the local
command and unconnected mode. This allows changes to the PS store to take effect. The module
will issue an OK response after the reset is complete and it is ready to receive commands once again.
ATZ and ATZ0 signify reset and emerge into the current mode (see command ATI14). ATZ1 to ATZ4
instructs the module to reset and then emerge into the appropriate boot mode. Note that S Reg 103
specifies the boot mode from cold.
Response: <cr,lf>OK<cr,lf> and OK is returned after the RESET
12. AT&W {Write S Registers to Non-volatile Memory}
Writes current S Register values to non-volatile memory so that they are retained over a power cycle.
Response: <cr,lf>OK<cr,lf>
Or
Response: <cr,lf>ERROR nn<cr,lf>
