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13.0 Usage Scenarios
(Continued)
13.2 SCENARIO 2: AUTOMATIC POINT-TO-POINT
CONNECTION
LMX9820 at both sides.
Example:
Serial Cable Replacement.
Device #1 controls the link setup with a few commands as
described.
If step 5 is executed, the stored default device is connected
(step 4) after reset (in Automatic mode only) or by sending
the command “Connect to Default Device”. The command
can be sent to the device at any time.
If step 6 is left out, the microcontroller has to use the com-
mand “Send Data” instead of sending data directly to the
module.
Figure 19. Automatic Point-to-Point Connection
Microcontroller
LMX9820
Air
Inquiry
Inquiry Request
Inquiry Response
Inquiry Result
Establish SDP Link
Transparent Mode
SDP Link Request
SDP Link Accept
SDP Link Established
Connected
on Port R
Service Browse
Browse Result
Release SDP Link
SDP Link Released
Service Browse
Service Response
Release SDP Link
Release Confirm
SPP Link Request
SPP Link Accept
Establish SPP Link
Link Established
LMX9820
Transparent Mode
Serial Device #1
Inquiry
1. Devices in Range
Inquiry Result
2. Choose the Device
3. Which COM Port is
available
Establish SDP Link
SDP Link Established
Service Browse
RFComm Port = R
Release SDP Link
SDP Link Released
4. Create SPP Link
Establish SPP Link
Connected on Port L
to Port R1 on Port L2
Transparent Mode
6. Switch to
to Port R on Port L
Microcontroller
Serial Device #2
5. Connect on Default
Store Default Device
(Optional)
Device Stored
Storing Default Device
Device Stored
1. Port R indicates the remote RFComm channel to connect to. Usually the result of the SDP request.
2. Port L indicates the Local RFComm channel used for that connection.
No Bluetooth commands necessary;
only “connected” event indicated to controller
Bluetooth device controls link with
a few commands
Interface
Transparent
Raw Data