How to prevent data loss while sending data over bluetooth

RE: How to prevent data loss while sending data over bluetooth

Ulrich Myhre — Mon, 19 May 2014 07:33:20 GMT

When NRF_SUCCESS is returned the data is queued for transfer. Depending on the no. packets per event supported on the peer, this might be 1-6 connection intervals into the future. If the peer has full buffers, it will also NACK packets until it is free to receive.

When the packet(s) have/has actually been sent over the air, and they've been ACKed by the peer, you will receive a TX_COMPLETE event with a count of how many packets that were transmitted. This is what you should keep track of if you need to continue transmissions where you left off after a disconnection.

RE: How to prevent data loss while sending data over bluetooth

mira67 — Fri, 16 May 2014 21:39:16 GMT

Does that mean the data is transferred to master device when the err_code is "NRF_SUCCESS"? Or we have to build application level to make sure no data loss during the BLE transmission. Thanks.

RE: How to prevent data loss while sending data over bluetooth

Ole Morten — Mon, 04 Nov 2013 14:33:24 GMT

You must check the error code when trying to send data. If you don't get NRF_SUCCESS back, you need to resend the data from your application if you actually want to transmit it.

There have been several discussions on this site about how to get high throughput, so I'd recommend you to search around a little if you still have trouble with this. The reply I gave you on this question is still valid, so I'd recommend you to instead implement something like that.

RE: How to prevent data loss while sending data over bluetooth

John Kelley — Tue, 29 Oct 2013 07:35:58 GMT

You may want to get rid of your divide for the d variable and simply replace your for loop with: for(k=0;k<length;k+=20)

M0 has no hardware divide and addition is always faster.