HC05 Firmware

Hello,

Let's take a look to the HC05 firmware.

This one offers a wider range of AT command set.

With these AT commands you can set the module to master or slave devices.

I will not describe all the AT command since you can refer to online documentation.

Before going on, you had to know that entering in the AT mode is a bit more difficult with HC05 firmware.

This firmware provides 2 ways to activate AT mode :

The first way is described as below :

• set low level on PIN34
• Supply power to the module
• set high level on PIN34

Then the module will enter on AT mode without your configured baud rate (default : 9600 8N1)

The second way :

• set high level on PIN34,
• Supply power to the module

The module will ALWAYS enter in AT mode with a 38400 baud rate (8N1).

The second way is kind useful if you don't remember your configured baud rate.

As you probably notice, AT mode can be reached only when PIN34 is high.

Moreover sending AT commands is different from the HC06 firmware (Linvor). In HC05 firmware you have to send CR and LF after each command.

For your information, here comes some useful AT commands :

• AT\r\n AT test command should respond OK\r\n
• AT+ROLE=1\r\n Set master mode
• AT+ROLE=0\r\n Set slave mode
• AT+VERSION?\r\n Get the firmware version
• AT+UART=115200,1,2\r\n Set the baud rate to 115200 (8E2)
• AT+PIO=10,1\r\n Set PIO10 to high level
• …

Further information can be found in this documentation.

That's it for now...

The next article will answer this question : Can I upload a HC05 onto a linvor module ?