DSD TECH HC-05 Bluetooth Serial Pass-through Module Wireless Serial Communication with Button for Arduino

Datasheet : Download

AT Command Doc: Download

There are  2 way to enter the AT Command mode:

way 1:

Step 1: Input low level to PIN34->EN PIN. (it can also be floating)

Step 2: Supply power to the module. 

Step 3: Input high level to the EN PIN(PIN34)(you can press the button this do this action,if you buy HC-05 from DSD TECH) 

Then the module will enter to AT mode. The baud rate is as same as the communication time, default is  9600

Way 2: 

Step 1: Connect PIN34(EN PIN) to the power supply PIN.or always press the button .

Step 2: Supply power to module

Then the module will enter to AT module. But at this time, the baudrate is always 38400. In this way, user should change the baud rate at the AT mode, if they forget the communication baud rate.

Features:

• Bluetooth module HC-05 Master and slave Two in one module
• Use the CSR BC417 mainstream bluetooth chip, bluetooth V2.0 SPP protocol standards
• Module working voltage 3.6 V to 6V
• Default rate of 9600,default pin:1234, the user can be set up.click the button into AT MODE
• Can be switched via AT commands as master or slave mode , the device can be connected via AT commands specified       

Description:
 The Core module is HC-05 bluetooth 2.0 module. By using this Bluetooth module, you can quickly add Bluetooth features to your arduino project. The factory setting is slave mode, but you can set this module to master mode so that you might be able to connect to other Bluetooth 2.0 devices. Please note: This is a classic Bluetooth 2.0 module, it is not compatible with iphone or ipad If you need to use iphone or ipad to control your arduino project. You may need a Bluetooth 4.0 ble module (such as SH-HC-08 Bluetooth 4.0 ble module)    

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