Long time data forwarding pause

[TGuanLa]

Hello All,

I have a problem when I build my project from sample central_uart &  peripheral_uart.

I have two nrf5340 called A and B. B scans the broadcast to A to establish a connection. Then my nrf52840(C) connects B.

A sends data to B, and B forwards data to C.

I use sniffer to capture the data packet.

I found that there is always Long time data forwarding pause of connection between B and C.

Is there any solution to solve this problem? 

Thank you.

[Edvin]

Hello,

What do you mean by a long time? Are we talking seconds? I didn't understand exactly what I was looking at in the sniffer trace screenshot. Which of the connections is that? B->C? If so, I can't tell when A->B was sent.

How do you handle the forwarding inside B? Can you send some snippets?

And finally, what are your connection parameters? Connection interval, mainly.

Best regards,

Edvin

[TGuanLa]

Sorry for the delaying. I have tested more data. The problem is that I set the connection interval is 7.5ms, but it doesn't work when sending data. After several data packets, there is always a long delay of B. 

The data of image is between A and B. B is master and A  is salve.

Now  A B and C all work at PHY2M. It seems that every time interval the ratio sends all data packets in  ACL_TX buffer. Then B ratio works for anonther connection. Is there any solution to Shorten the time interval？My project needs low latency less than 4ms for every data packects.

Thanks!

[Edvin]

TGuanLa said:

My project needs low latency less than 4ms for every data packects.

Seeing that a connection interval is minimum 7.5ms, I think you will have a hard time setting a hard limit on maximum 4.5ms. But it should be possible to do it faster than many connection intervals. Is it possible for me to reproduce what you are seeing? If so, can you please upload your projects here so that I can replicate it using some DKs?

BR,

Edvin

[TGuanLa]

1208.central_uart.zip

Here is my code for B.

7457.peripheral_uart_throughput_test.zip

Here is my project for A.

[Edvin]

And what would I use for C? Is that another B?

[TGuanLa]

Hi，

I use Bluetooeh Low Energy from nRF Connect for Desktop to control C(nrf52840).