User's Manual

Operating the RB540MB for Tx/RX (one-way A2DP)

The RB540 has optional firmware for TX/RX (one-way A2DP). This firmware allows the user to

establish a Bluetooth proprietary connection between two RB540 Modules. After a Bluetooth

connection is established between two RB540MB, the user can use the modules as one-way TX/RX

communication.

The following will explain how to use the RB540MB switches to control the RB540 module with

the standard TX/RX (one-way A2DP) firmware.

Connect an USB cable into both RB540MB boards.

1. Power ON RX: Plug your speakers into the SPK1 Stereo Jack. Turn on the PSW1 on

RB540MB RX. A “du-du-du” sound will play for power on indication. LED1-2 will flash

alternately, LED4 stays lit. RB540 RX will automatically enter discoverable mode at all times.

2. Power ON TX and initiate Pairing: Plug the microphone into MIC1A. Turn on the PSW1 on

RB540MB TX. LED1-2 will flash alternately, LED4 stays lit. In first 10 seconds, RB540 TX

will try to connect to last paired RX, the reconnection will be established in couple seconds. If

no reconnection established in 10 seconds, RB540 TX will automatically enter pairing mode to

search a new RX. After paired, a “du-du” sound will play in RX, and LED1, LED4 will lit on

both TX and RX RB540MB boards.

Note: Suggested always to power on RX first, in order to shorten TX pairing time.

3. Now you can use TX as talking or music source, and hear the sound from RX.

4. Volume change on TX: There are 21 levels of volume up and down on TX. SW2 is volume +

and SW1 is volume -. Button SW2 and SW1 can be pressed step by step or continuously.

Note: Volume change function not supported in RX.

5. Clear Pairing Record: Long press TX SW4 for 10 seconds to clear the previous pairing record.

Note:

1. Power cycle RB540MB RX, the module will automatically enter discoverable mode for any

available TX in the range.

2. Power cycle RB540MB TX, the module will first try to connect to last paired RX for 10

seconds, if no connection established in 10 seconds, TX will automatically enter pairing

mode for searching a new RX.

3. No pairing button needed in this firmware revision, all pairing connection will be

automatically handled in couple seconds.