FAQ about the Bluetooth module

When we purchased the module for testing, we will encounter some problems , for the Frequently Asked Questions , Feasycom company sorted out it of customers , please read it in the bellow.

 How does the Bluetooth module perform a firmware upgrade?

At present, some of the series of upgraded modules of Feasycom company have three upgrade modes: serial port upgrade, USB upgrade, and over the air upgrade (OTA). Other modules can only be burned through Jlink or SPI interface. 

The modules that support serial port upgrade are: FSC-BT501, FSC-BT803, FSC-BT816S, FSC-BT821, FSC-BT822, FSC-BT826, FSC-BT836, FSC-BT906, FSC-BT909, etc. 
The modules that support USB upgrade are: FSC-BT501, FSC-BT803 , BT802 , BT806 
The modules that support the air upgrade are: FSC-BT626, FSC-BT816S, FSC-BT821, FSC-BT826, FSC-BT836, FSC-BT906, FSC-BT909, etc. 

What is the transparent transmission mode?

The transparent transmission mode is transparent transmission of data between the module and the remote device, and the transmitting end does not need to send an instruction or increase the header of the packet, and the receiving end does not need to parse the data.

(In transparent mode, the AT command is turned off by default, and you need to enter the command mode by pulling up the specified IO)


How to send AT command in transparent mode?

 When the module is in transparent transmission mode, it can be switched to the command mode by pulling the specified I/O port high. When the command is sent, the IO can be pulled down and then switched to the transparent mode.

When the module is not connected, it is in the command mode by default. After the connection is successful, it is in the transparent transmission mode by default.

 Why can't the phone connect to the module in the Bluetooth settings? 

  The phone settings only support certain types of Bluetooth peripherals, such as Bluetooth headsets, stereos, keyboards, and more. If it is not a type of peripheral supported by the mobile phone (such as a data transmission device)

You can't connect directly in the settings, you need to install the “FeasyBlue” APP to connect the test.


What is the master-slave integration? 

A module program can be used as a master device to search for a connected slave device, or as a slave device to be discovered and connected by other master device modules.  

In the later stages, we will continue to update frequently asked questions about Bluetooth modules. If you have any ideas or questions, please feel free to contact us. 


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