Bluetooth HC-05 Transceiver

Bluetooth Master or Slave capable Module

• Worldwide 2.4GHz ISM band operation
• Bluetooth module HC-05 Master and slave in one module
• Uses the CSR bluetooth chip, bluetooth V2.0 protocol standards
• Module working voltage 3.3 V, has onboard regulator
• Module can direct connect to Arduino
• Default Baud Rate 9600

HC-05 PinOut :

• KEY: If brought HIGH before power is applied, forces AT Command Setup Mode. LED blinks slowly (2 seconds)
• VCC: +5 Power
• GND: System / Arduino Ground
• TXD: Transmit Serial Data from HC-05 to Arduino Serial Receive. NOTE: 3.3V HIGH level: OK for Arduino
• RXD: Receive Serial Data from Arduino Serial Transmit
• STATE: Tells if connected or not

AT Command Listing

1 AT Test UART Connection
2 AT+RESET Reset Device
3 AT+VERSION Querry firmware version
4 AT+ORGL Restore settings to Factory Defaults
5 AT+ADDR Query Device Bluetooth Address
6 AT+NAME Query/Set Device Name
7 AT+RNAME Query Remote Bluetooth Device’s Name
8 AT+ROLE Query/Set Device Role
9 AT+CLASS Query/Set Class of Device CoD
10 AT+IAC Query/Set Inquire Access Code
11 AT+INQM Query/Set Inquire Access Mode
12 AT+PSWD Query/Set Pairing Passkey
13 AT+UART Query/Set UART parameter
14 AT+CMODE Query/Set Connection Mode
15 AT+BIND Query/Set Binding Bluetooth Address
16 AT+POLAR Query/Set LED Output Polarity
17 AT+PIO Set/Reset a User I/O pin
18 AT+MPIO Set/Reset multiple User I/O pin
19 AT+MPIO? Query User I/O pin
20 AT+IPSCAN Query/Set Scanning Parameters
21 AT+SNIFF Query/Set SNIFF Energy Savings Parameters
22 AT+SENM Query/Set Security & Encryption Modes
23 AT+RMSAD Delete Authenticated Device from List
24 AT+FSAD Find Device from Authenticated Device List
25 AT+ADCN Query Total Number of Device from Authenticated Device List
26 AT+MRAD Query Most Recently Used Authenticated Device
27 AT+STATE Query Current Status of the Device
28 AT+INIT Initialize SPP Profile
29 AT+INQ Query Nearby Discoverable Devices
30 AT+INQC Cancel Search for Discoverable Devices
31 AT+PAIR Device Pairing
32 AT+LINK Connect to a Remote Device
33 AT+DISC Disconnect from a Remote Device
34 AT+ENSNIFF Enter Energy Saving mode
35 AT+EXSNIFF Exit Energy Saving mode

Error Codes

0 Command Error/Invalid Command
1 Results in default value
2 PSKEY write error
3 Device name is too long (>32 characters)
4 No device name specified (0 length)
5 Bluetooth address NAP is too long
6 Bluetooth address UAP is too long
7 Bluetooth address LAP is too long
8 PIO map not specified (0 lenght)
9 Invalid PIO port Number entered
A Device Class not specified (0 lenght)
B Device Class too long
C Inquire Access Code not Specified (0 lenght)
D Inquire Access Code too long
E Invalid Iquire Access Code entered
F Pairing Password not specified (0 lenght)
10 Pairing Password too long (> 16 characters)
11 Invalid Role entered
12 Invalid Baud Rate entered
13 Invalid Stop Bit entered
14 Invalid Parity Bit entered
15 No device in the Pairing List
16 SPP not initialized
17 SPP already initialized
18 Invalid Inquiry Mode
19 Inquiry Timeout occured
1A Invalid/zero lenght address entered
1B Invalid Security Mode entered
1C Invalid Encryption Mode entered

Additional information