JY-MCU Arduino Bluetooth Wireless Serial Port Module. These modules are available in master (HCARDU0064) and slave (HCARDU0004) versions. Please see FAQ section on our support forum here before purchasing one of these modules.

Default password: 1234

Baud rate: 9600

Dimensions: 1.73 in x 0.63 in x 0.28 in (4.4 cm x 1.6 cm x 0.7 cm)

PINOUT
1.....VCC
2.....GND
3.....TXD
4.....RXD

AT Commands:

Module must be disconnected (Led flashing) to issue AT commands.

Communication Test :
Send: AT
Response: OK

Change Baud Rate:
Send: AT+BAUD<b>

<b>......Baud
1......1200
2......2400
3......4800
4......9600
5......19200
6......38400
7......57600
8......115200

E.g.
Send: AT+BAUD7
Response: OK57600

Change Bluetooth Device Name:
Send: AT+NAME<devicename>

E.g.
Send: AT+NAMEHobbComp
Response: OKHobbyComp

Change Pincode:
Send : AT+PINxxxx
Response: OKsetpin

Example code and manual available on our support forum here.