DVK-BTM521 Laird Technologies, DVK-BTM521 Datasheet - Page 35

• Manufacturer Part Number: DVK-BTM521
• Description: BT MM DEV KIT
• Manufacturer: Laird Technologies
• Type: Transceiver, Bluetoothr

Specifications of DVK-BTM521

• Frequency: 2.4GHz
• Interface Type: RS-232
• Processor Series: BTM521
• Silicon Manufacturer: Laird Technologies
• Kit Application Type: Communication & Networking
• Application Sub Type: Bluetooth
• Kit Contents: Development Board & Software Tools
• Features: Supports CSR
• Rohs Compliant: Yes
• For Use With/related Products: BTM521
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: DVK-BTM521

BTM520/521
Bluetooth
AT COMMAND SET
REFERENCE
35 www.lairdtech.com
®
Multimedia Plus Module
3. A2DP (Advanced Audio Distribution Profile)
2.9 SPP – S Registers
The “Advanced Audio Distribution Profile” is used for unidirectional transmission of high quality audio
streams between two Bluetooth devices. A2DP must be enabled by setting S 102 to a value of 128.
Also, an A2DP role must be assigned to a BTM module, either source or sink. After this has been done,
the settings need to be stored by AT&W followed by ATZ.
An incoming A2DP connection request is accepted automatically if a valid link key for the paging device
exists. If no link key is available, Secure Simple Pairing (SSP, BT2.1) or legacy pairing (BT2.0 or earlier) is
carried out, depending on the Bluetooth version of the paging device.
After an A2DP connection has been established, the module remains in AT Command mode. S Register
531 is ignored for A2DP connections.
Version 1.2 of A2DP is supported.
The A2DP service record contains an optional field which indicates the A2DP supported features of
a device. This feature field can be set by S312 for a sink and by S313 for a source. Please refer to
Table 3.16 for details.
Table 3.17 gives an overview on supported A2DP features on a BTM device.
Table 3.12 lists supported A2DP codec types.
A2DP Feature
1.
M: mandatory
A2DP Codec Type
1.
2.
3.
4.
M: mandatory
O: optional
S Registers for SPP are summarized in Table 3.10.
Register
S0
S100
Audio Streaming
SBC
MPEG-1,2 Audio
MPEG-2,4 AAC
ATRAC family
Default Range
0
15
Table 3.12: A2DP Supported Codec Types on BTM5xx
Table 3.11: A2DP Supported Features on BTM5xx
-1..15
0..15
Support in SRC (Audio Source)
Support in SRC (Audio Source) Support in SNK (Audio Sink)
Spec.
M
O
O
O
Spec.
Table 3.10: S Registers for SPP
M
Description
Number of RING indication before automatically
answering an incoming connection. A value of 0
disables autoanswer. If -1, then autoanswer on one
RING and do NOT send RING/CONNECT response
to the host. This emulates a serial cable replacement
situation Setting values >= 0, resets S Register 504 to
0 and <0 forces 504 to 1.
If S0 <> 0 and S100 <> 0 then S0 must be < S100. If
a value is entered which violates this rule, then ERROR
29 is sent in response.
If S504 =1 then this register will return -1, regardless
of the actual value stored in non-volatile memory.
Number of RING indications before an auto
disconnection is initiated. A value of 0 disables
this feature. If S0 <> 0 and S100 <> 0 then S0
must be < S100. If a value is entered which violates
this rule, then ERROR 29 is sent in response.
BTM5xx
Yes
No
No
No
BTM5xx
Yes
Spec.
M
O
O
O
Support in SNK (Audio Sink)
Spec.
M
BTM5xx
Yes
No
No
No
BTM5xx
Yes
Laird Technologies