Apps Connect and receive file from hardware device to android app

[Batt]

Hi everybody,

I have a problem when I try to connect and receive file (String text) from hardware device. Now I have a device connect to my phone by USB cable, and have a button on device, when I press button on devices, device will send a data (String, text) . Now I need my app on my app receive and display data sent from device. Anybody have a example or document about it, please share or guide for me.

Thanks you very much !