How can I connect two nRF52840 to transfer large data files?

RE: How can I connect two nRF52840 to transfer large data files?

ovrebekk — Tue, 30 May 2017 12:00:43 GMT

The packet transmission is handled by the function called char_notification_send(..) on line 218 of amts.c
Right now it is only sending a static buffer called uint8_t data[256] over and over, but you can replace this variable with some data of your own. The "file" size is set by the AMT_BYTE_TRANSFER_CNT define, which you can also change if you want to change the transfer size.

The transmission of dummy data is initiated by the nrf_ble_amts_notif_spam(&m_amts) function. You should probably add a similar function that allows you to pass some data to the amts.c module, rather than just sending dummy data, and have the char_notification_send(..) function break your data into pieces and send them one after the other.

RE: How can I connect two nRF52840 to transfer large data files?

Gót G?y — Fri, 26 May 2017 07:45:31 GMT

Can you teach me to do this ?

RE: How can I connect two nRF52840 to transfer large data files?

ovrebekk — Mon, 03 Apr 2017 06:42:24 GMT

Hi Gerry

There is a throughput example in the SDK that can be used as a starting point if you want to maximize the throughput over BLE: \nRF5_SDK_13.0.0\examples\ble_central_and_peripheral\experimental\ble_app_att_mtu_throughput\

The example shows how you can enable important features such as data length extension, connection event extension, and how you can increase the GATT MTU size.

Out of the box it is only set up to send dummy data, so it will need some modifications to send an actual file.

Best regards
Torbjørn

RE: How can I connect two nRF52840 to transfer large data files?

Frederik — Fri, 31 Mar 2017 06:59:57 GMT

Maybe you can get something out of the throughput example devzone.nordicsemi.com/.../ .

RE: How can I connect two nRF52840 to transfer large data files?

Gerry — Thu, 30 Mar 2017 21:53:39 GMT

Sorry for the vagueness. The intent is to use it for small to moderate data transfers, yet understand how it handles large files (firmware update of the host FW) as needed. Just looking to see what we can get out of the 2Mb link.

RE: How can I connect two nRF52840 to transfer large data files?

awneil — Thu, 30 Mar 2017 21:38:08 GMT

Also note that none of the protocols supported by this chip is optimised for either large data volumes or high transmission rates

The nRF52840 is an advanced multi-protocol SoC ideally suited for ultra low-power wireless applications.

So - are you sure this is the right chip for your job ... ?

RE: How can I connect two nRF52840 to transfer large data files?

awneil — Thu, 30 Mar 2017 21:14:21 GMT

That's a very vague question.

Sending a large file is no different, in principle, from sending a small or medium one - it's all just "more of the same"

So what is it, exactly, that you're stuck on?