1, serial module operating voltage 3.3V.
2, the baud rate can be set 2400,4800,9600,19200,38400,57600,115200,230400
3 core module size: 28mm x 15 mm x 2.35mm.
1, led pin indicates Bluetooth connection status, the output pulse Bluetooth connectivity, high output indicates that Bluetooth is connected and turned on the port
2, the power supply voltage of 3.3V, the absolute prohibition of reversed power! Absolute prohibition of more than 3.6V power!
3, the interface level 3.3V, can be connected to various microcontroller (51, AVR, PIC, ARM, MSP430) the 5V MCU best a 1K resistor in series with the module directly connected, the conversion of the published specifications schematic bottom, without MAX232 MAX232!
4, Effective distance of 3 meters, more than 3 m are possible, but do not do this from the connection quality assurance
The factory default parameters:
Slave, baud rate: 9600, n, 8,1. Passkey: 1234.
Second, AT command set as follows:
Note: HC-09 on power-up test, the module requires 7S time to complete the initialization, after the completion of the initialization module indicator will blink.
1, test communications
Send: AT (return OK, one second left and right)
2, change the Bluetooth serial communication baud rate
Send: AT + BAUD2
Back to: OK2400
2 ——— 2400
3 ——— 4800
4 ——— 9600
5 ——— 19200
6 ——— 38400
7 ——— 57600
8 ——— 115200
9 ——— 230400
Note: HC-09 on the baud rate is different from the HC-06, HC-09 baud rate of a minimum of 2400, up to 230400
AT command set baud rate, the next power do not need to set up and can be powered down to save the baud rate.
3, change the Bluetooth name
Send: AT + NAMEname
Back to: OKname
Example: Sending AT + NAMEbill_gates
The Bluetooth name changed to bill_gates
Read the Bluetooth name
Send: AT + NAME
Returns: NAME = name
Example: Send: AT + NAME
In return: NAME = bill_gates \ r \ n
Parameter name: To set the current name, the name of the Bluetooth search. 32 characters or less.
The parameters can be powered down to save, simply modify the time. PDA the end refresh can see the Bluetooth name changed.
4, change the Bluetooth pairing password
Send: AT + PINxxxx
Example: Sending AT + PIN8888
The Bluetooth pairing password to 8888, module paired at the factory default password is 1234.
To read Bluetooth pairing password
Send: AT + PIN
Back: PIN = xxxx
Example: send AT + PIN
To return PIN = 8888 \ r \ n
Parameter xxxx: To set a passcode, 4 bytes