I’m trying to develop a device which has a bluetooth module which can be connected to via an application, and have its files downloaded which are stored on an SD card on the device.

The idea is that the device will collect information, write said information to an SD card as a .csv file, and have the capability to have it downloaded to an external device (like a pc) over the bluetooth connection.

I’m still relatively new to bluetooth, so I am a little unsure on what the standard protocol is to achieve this. The steps to be followed are:

Device collects data and saves to SD card file system as .csv file

User connects to device over bluetooth using built application. The application can see what is on the SD card

User selects a file and presses “download”

File downloads to users device (eg pc)

Now, this file is already stored on the file system as a CSV file. When i want to download it, how do I do that? Do I stream the raw contents of the file over bluetooth to the end device? Or do I convert it to something like a binary and send that? Or is there something else I should focus on? My first assumption is that you would send a binary version of the file in byte chunks.

If you have any resources I should also read up on that would be greatly appreciated.