Simultaneous communication as central and perihperal for the nRF52840

[jinvers]

Hello,

I have to develop a new device that has to connect as a central device to three sensors, and has to connect as a peripheral to a smartphone. The type of connection would be 1Mbps PHY. The sequence of events would be the next:

 1.- Capture the information of sensor 1.

2.- Repeat the information of sensor 1 to the smartphone.

3.- Repeat the former steps for sensor 2 and sensor 3.

The quantity of information is quite long for each sensor (around 110KBytes), so I will have to divide the communication of the buffer information in many packets. What do you think could be the maximum packet size I could receive and send using the nRF52840 and the present SoftDevice version?

There is then a problem about the time delay between the capture of the information of the three sensors and the reception in the smartphone. For reducing the time delay one option would be resend a packet to the smartphone at the same time that it's readed from one sensor. Do you think the only way to do that would be assembling 2 modules based on nRF52840? Or is it possible to interleave the Rx as central with the Tx as peripheral?

Thank you very much in advance.

Best Regards,

Joel Invers

[Kenneth]

Hi,

Before going into details here, can you describe a bit about the latency requirements (e.g. 100ms?) you have from sensors to relay, and from sensors all the way to the phone (e.g. 200ms)? Also please state the throughput requirements you have from each peripheral (e.g. 10Kb/s) to the relay, and from the relay to the phone (e.g. 30Kb/s)? I just want to understand if this application is possible. Is there any reason why the sensors can't connect directly to the phone?

Kenneth