Large data transfer over ble.

[Thomas]

Hi,

I would like to have a system such as follows:

• Taking sensor data storing it locally till around 100 samples (Once per second)
• Log this data to the SD with a time stamp
• Then storing this data to an external SD card. (Utilising the fatfs example code in the SDK) Around  2 Mbytes
• I then want a mobile device to request this data.

What therefore, is the best way of transferring the data from the SD card to BLE to be picked up by the mobile application.

Do I need to set up a GATT connection and wait on a notification change that I set in the Nordic board?

If so is there an example of this or a good starting point.

Would this post be a good starting point? : https://devzone.nordicsemi.com/f/nordic-q-a/553/dealing-large-data-packet-s-through-ble

If so what example is good to work from. Thanks

[Simonr]

Hi

It seems to me like you might be pushing the upper limit of what you will be able to transfer using BLE here. I suggest you take a look at this blog post, which shows you how to achieve maximum throughput, and also provides source code for a project doing this.

Best regards,

Simon

[Thomas]

Hi Simonr,

I don't think I am pushing the limits as I don't need it to be all done in a single second. Although faster is better. Would you say my outlined approach is correct though?