LMX9820ASM datasheet(33/44 Pages) NSC

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13.0 Usage Scenarios (Continued)

13.2 SCENARIO 2: AUTOMATIC POINT-TO-POINT

CONNECTION

LMX9820A 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 “Connect to Default Device” command. The command

can be sent to the device at any time.

If step 6 is left out, the microcontroller has to use the “Send

Data” command, instead of sending data directly to the

module.

Figure 20. Automatic Point-to-Point Connection

Microcontroller

LMX9820A

Air

Inquiry

Inquiry Request

Inquiry Response

Inquiry Result

Establish SDP Link

Transparent Mode

SDP Link Request

SDP Link Accept

SDP Link Established

Connected

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

on Port R

LMX9820A

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

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