Transfer big file over BLE

[Michal]

Hi, I already have device that plays audio from sd card. New feature is needed that user can send MP3 file to device from mobile phone that will be stored in sd card and then played on request. So I am not talking about streaming. I was wondering if there exists nordic example on reliable file sending, that would include ble service for nrf and code for mobile? I am thinking of reusing DFU code. It should provide me all features I need like restarting interrupted sending and missed/corrupted bytes detection base on crc. I am just wondering if DFU doesnt have too much overhead and maybe there is faster/better way to send big file?

Michał

[Jørgen Holmefjord]

Hi ,

Have you seen the Object Transfer Service Server Application and Object Transfer Service client examples? We do not have any implementation of this on the mobile side, but since OTS is a Bluetooth SIG specified service there might be some implementations out there already.

You could also have a look at the nrf52-ble-image-transfer-demo and Android-Image-Transfer-Demo, which implements a custom service to transfer an image.

Best regards,
Jørgen

[Jørgen Holmefjord]

I'm not aware of any current plans to implement this on the mobile side. OTS requires L2CAP Connection oriented Channels, which might not be supported until Android Q is released.