Mainstream CSR Bluetooth chip, Bluetooth V2.0 protocol standards
2, serial module operating voltage 3.3V.
3, the baud rate can be set 2400,4800,9600,19200,38400,57600,115200,230400 user
4 core module size: 28mm x 15 mm x 2.35mm.
5 Operating Current: power input is terminated with a resistance of 5 ohms, use a multimeter to test a variety of state power of the line
The module is paired with the adapter
Test current is 25MA
Module paired with the adapter to connect and send data
Test current is 27MA
The module does not paired with the adapter
Test current is 15MA
6, Sleep current: Sleep
7 for the GPS navigation system, utility meter reading system, the industrial field, collecting and controlling system.
8, with a Bluetooth laptop computer to the Bluetooth adapter, PDA and other devices to seamlessly connect
Paired only as a fixed baud rate of the serial port can be used as long as it is “fixed baud, 8 data bits, no
Parity “communication format serial device can directly replace the original wired serial without the need to modify the program such as data sets,
Smart car, serial printer, outdoor the lattice strip screen control.
Paired with your computer : suitable for a computer with the device through Bluetooth serial communication, use serial
Paired with the phone : For the phone with devices via Bluetooth serial communication using serial
Paired with a Bluetooth host : suitable for two devices directly through the Bluetooth serial communication, such as single-chip microcontroller, wired serial
With SCM room, use serial
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, open to effective distance of 3 meters, more than 3 m are possible, but do not do this from the connection quality assurance
After pairing, when the serial line used to support the eight-digit, 1 stop bit, parity or no parity
Support Bluetooth connection is not established by the AT command set the baud rate, name, pairing password, power-down save parameters set. Bluetooth connection automatically switch to transparent mode
7, small size (2.7cm * 1.3cm) the factory chip production to ensure the quality of the patch.
baud rate conversion, because the receiver and the sender can choose their own baud rate, in a small amount of data can be used as a baud rate conversion equipment.
The module and SCM follow the following connections (Bluetooth module voltage of 3.3V):
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 needs the 7S time to complete the initialization, after the completion of the initialization module indicator will blink.
1, test communications
sent: AT (return OK, one second left and right)
2, change the Bluetooth serial communication baud rate
sent: the AT + BAUD2
2 ——— 2400
3 ——— 4800
4 ——— 9600
5 ——— 19200
—– —- 38400
7 ——— 57600
8 ——— 115200
Note : HC-09 on the baud rate is different from the HC-06, HC-09 baud rate of a minimum of 2400, up to 230,400,
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
Example: Send the AT + NAMEbill_gates
The Bluetooth name changed to bill_gates
Read Bluetooth Name
Send: AT + NAME
return: name = name
cases will: Send: AT + NAME
return: the NAME = bill_gates \ r \ n
Parameter name: To set the current name, that name Bluetooth is searched. 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: Send AT + PIN8888
The Bluetooth pairing password to 8888, the module factory default passkey is 1234.
Read Bluetooth pairing password
Send: AT + PIN
return: PIN = xxxx
Example: Sending AT + PIN
return PIN = 8888 \ r \ n
parameter xxxx: To set a passcode, 4 bytes
HC-09 is currently only a slave.