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How Do I Connect Two Modules Together?
Procedure to connect two BT44-xxx modules together
The BT44-xxx modules are designed for embedded application. They are programmable for either SLAVE or MASTER Mode. To connect two BT44-xxx modules together please see the following procedure:

STEP 1: Connect each module to a PC and run Hyperterminal
STEP 2: Choose one device as a master (MODULE A)
STEP 3: Power up the MODULE A and HIT ESC within 5 seconds of power-up The module returns

+ OPEN: 0

You should be in the command mode
STEP 4:Using HyperTerminal from the Command set-up mode Set device A as a MASTER
AT+ROLE=1  This will set this device as a master
Note:1 The default mode is Slave
STEP5: Inquire remote devices
Using AT+INQ
Note: This command commences the discovery process to detect any BT device in the neighborhood. Completion of this command may take up to 30 seconds. The command may be terminated by sending the AT+CANCEL command.
The response to the above command is:
+INQRESU:0005164801E6 Where the data following the colon is one example of the Bluetooth address of one of the devices in the neighborhood .

STEP6: Then Set the MASTER (Module A) devices with the appropriate BD address of the slave device known as the remote address (RADDR)
. First wait for the discovery process to complete and the module will return
+INQCOMP This will indicate that the Inquiry process has terminated.
Then type
AT+RADDR= BT address (the specific device you wish to pair determined from the AT+INQ Command).
The module will remain bound to this address until the AT+CLEARADDR is run or the module is powered off and then back on again.
Step 7: To remember the slaves module address please set the bind command AT+BIND=
Note: The default mode is to drop pair. The drop pair function occurs when the module is power-off then back on or the master drops pairing. This will allow another master to commence a discovery process and connect to the module (slave) device.

If the device is set-up as always paired (Bind=1) then the module will only communicate with the specific master whose address it has been bonded to even after power off and power-on. This mode is useful for application where a cable replacement function is the required. To communicate to a different master the module must have the bonded address cleared. This is accomplished by running the AT+CLEARADDR command.

If a module has been operated with bind=1 and then subsequently the bind function is set to 0 the module will still remember the previous bound address. So if bind is re-enabled then device will re-connect to the previously bound master. To clear the memory please run the AT+CLEARADDR command.

This effectively simulates cable replacement between two modules.