HC Serial Bluetooth Products
User Instructional Manual
1 Introduction
HC serial Bluetooth products consist of Bluetooth serial interface module and Bluetooth adapter, such
as:
(1) Bluetooth serial interface module:
Industrial level: HC-03, HC-04(HC-04-M, HC-04-S)
Civil level: HC-05, HC-06(HC-06-M, HC-06-S)
HC-05-D, HC-06-D (with baseboard, for test and evaluation)
(2) Bluetooth adapter:
HC-M4
HC-M6
This document mainly introduces Bluetooth serial module. Bluetooth serial module is used for
converting serial port to Bluetooth. These modules have two modes: master and slaver device. The
device named after even number is defined to be master or slaver when out of factory and can’t be
changed to the other mode. But for the device named after odd number, users can set the work mode
(master or slaver) of the device by AT commands.
HC-04 specifically includes:
Master device: HC-04-M, M=master
Slave device: HC-04-S, S=slaver
The default situation of HC-04 is slave mode. If you need master mode, please state it clearly or
place an order for HC-O4-M directly.The naming rule of HC-06 is same.
When HC-03 and HC-05 are out of factory, one part of parameters are set for activating the device.
The work mode is not set, since user can set the mode of HC-03, HC-05 as they want.
The main function of Bluetooth serial module is replacing the serial port line, such as:
1. There are two MCUs want to communicate with each other. One connects to Bluetooth master
device while the other one connects to slave device. Their connection can be built once the pair is made.
This Bluetooth connection is equivalently liked to a serial port line connection including RXD, TXD
signals. And they can use the Bluetooth serial module to communicate with each other.
2. When MCU has Bluetooth salve module, it can communicate with Bluetooth adapter of
computers and smart phones. Then there is a virtual communicable serial port line between MCU and
computer or smart phone.
3. The Bluetooth devices in the market mostly are salve devices, such as Bluetooth printer,
Bluetooth GPS. So, we can use master module to make pair and communicate with them.
Bluetooth Serial module’s operation doesn’t need drive, and can communicate with the other
Bluetooth device who has the serial. But communication between two Bluetooth modules requires at
least two conditions:
(1) The communication must be between master and slave.
(2) The password must be correct.
However, the two conditions are not sufficient conditions. There are also some other conditions
basing on different device model. Detailed information is provided in the following chapters.
In the following chapters, we will repeatedly refer to Linvor’s (Formerly known as Guangzhou HC
Information Technology Co., Ltd.) material and photos.
2 Selection of the Module
The Bluetooth serial module named even number is compatible with each other; The salve module
is also compatible with each other. In other word, the function of HC-04 and HC-06, HC-03 and HC-05
are mutually compatible with each other. HC-04 and HC-06 are former version that user can’t reset the
work mode (master or slave). And only a few AT commands and functions can be used, like reset the
name of Bluetooth (only the slaver), reset the password, reset the baud rate and check the version
number. The command set of HC-03 and HC-05 are more flexible than HC-04 and HC-06’s. Generally,
the Bluetooth of HC-03/HC-05 is recommended for the user.
Here are the main factory parameters of HC-05 and HC-06. Pay attention to the differences:
HC-05 HC-06
Master and slave mode can be switched Master and slave mode can’t be switched
Bluetooth name: HC-05 Bluetooth name: linvor
Password:1234 Password:1234
Master role: have no function to remember the last
paired salve device. It can be made paired to any
slave device. In other words, just set
AT+CMODE=1 when out of factory. If you want
HC-05 to remember the last paired slave device
address like HC-06, you can set AT+CMODE=0
after paired with the other device. Please refer the
command set of HC-05 for the details.
Pairing: The master device can not only make pair
with the specified Bluetooth address, like
cell-phone, computer adapter, slave device, but
also can search and make pair with the slave
device automatically.
Typical method: On some specific conditions,
master device and slave device can make pair with
Master role: have paired memory to remember
last slave device and only make pair with that
device unless KEY (PIN26) is triggered by high
level. The default connected PIN26 is low level.
Pairing: Master device search and make pair with
the slave device automatically.
Typical method: On some specific conditions,
master and slave device can make pair with each
other automatically.
each other automatically. (This is the default
method.)
Multi-device communication: There is only point
to point communication for modules, but the
adapter can communicate with multi-modules.
AT Mode 1: After power on, it can enter the AT
mode by triggering PIN34 with high level. Then
the baud rate for setting AT command is equal to
the baud rate in communication, for example:
9600.
AT mode 2: First set the PIN34 as high level, or
while on powering the module set the PIN34 to be
high level, the Baud rate used here is 38400 bps.
Multi-device communication: There is only point
to point communication for modules, but the
adapter can communicate with multi-modules.
AT Mode: Before paired, it is at the AT mode.
After paired it’s at transparent communication.
Notice: All AT commands can be operated only
when the PIN34 is at high level. Only part of the
AT commands can be used if PIN34 doesn’t keep
the high level after entering to the AT mode.
Through this kind of designing, set permissions for
the module is left to the user’s external control
circuit, that makes the application of HC-05 is very
flexible.
During the process of communication, the module
can enter to AT mode by setting PIN34 to be high
level. By releasing PIN34, the module can go back
to communication mode in which user can inquire
some information dynamically. For example, to
inquire the pairing is finished or not.
Default communication baud rate: 9600,
4800-1.3M are settable.
KEY: PIN34, for entering to the AT mode. KEY: PIN26, for master abandons memory.
LED1: PIN31, indicator of Bluetooth mode. Slow
flicker (1Hz) represents entering to the AT mode2,
while fast flicker(2Hz) represents entering to the
AT mode1 or during the communication pairing.
Double flicker per second represents pairing is
finished, the module is communicable.
During the communication mode, the module
can’t enter to the AT mode.
Default communication baud rate: 9600,
1200-1.3M are settable.
LED: The flicker frequency of slave device is
102ms. If master device already has the memory
of slave device, the flicker frequency during the
pairing is 110ms/s. If not, or master has emptied
LED2: PIN32, before pairing is at low level, after
the pairing is at high level.
The using method of master and slaver’s indicator
is the same.
Notice: The PIN of LED1 and LED2 are connected
with LED+.
Consumption: During the pairing, the current is Consumption: During the pairing, the current is
the memory, then the flicker frequency is 750m/s.
After pairing, no matter it’s a master or slave
device, the LED PIN is at high level.
Notice: The LED PIN connects to LED+ PIN.
fluctuant in the range of 30-40mA. The mean
fluctuant in the range of 30-40 m. The mean
current is about 25mA. After paring, no matter
processing communication or not, the current is
8mA. There is no sleep mode. This parameter is
same for all the Bluetooth modules.
Reset: PIN11, active if it’s input low level. It can
be suspended in using.
Level: Civil Level: Civil
The table above that includes main parameters of two serial modules is a reference for user
selection.
HC-03/HC-05 serial product is recommended.
current is about 25mA. After paring, no matter
processing communication or not, the current is
8mA. There is no sleep mode. This parameter is
same for all the Bluetooth modules.
Reset: PIN11, active if it’s input low level. It can
be suspended in using.
3. Information of Package
The PIN definitions of HC-03, HC-04, HC-05 and HC-06 are kind of different, but the package size
is the same: 28mm * 15mm * 2.35mm.
The following figure 1 is a picture of HC-06 and its main PINs. Figure 2 is a picture of HC-05 and
its main PINs. Figure 3 is a comparative picture with one coin. Figure 4 is their package size information.
When user designs the circuit, you can visit the website of Guangzhou HC Information Technology Co.,
Ltd. (www.wavesen.com
) to download the package library of protle version.
Figure 1 HC-06 Figure 2 HC-05
Loading...