[nRF51422] Presence of several nodes

[PW]

Hello. I have to detect presence of several nodes (max.8, battery supply). Addresses each of them will be known by master device. I don't have to send any data from central device to nodes, I'm interesting only receiving data from nodes. I wonder which mode should I choose? Device pairing or shared channel? Which one will be more energy efficient? Best regards, PW

[Asbjørn]

Are you asking about which radio protocol to use or have you selected this already?

[PW]

I forgot write that I'm using nRF51422 with s210. Meanwhile I use background scanning and 4 (so far) separate channels.

[Asbjørn]

If your data rate and latency requirement will allow you to share a channel with multiple nodes, that would be the best solution. If you end up with sending so often that you have trouble fitting all into one channel, you might be better with sharing or opening separate channels. For 8 sensors you could have them all in separate channels. Are you running the central device on battery as well or can you afford to keep this in RX for longer periods?

[PW]

Central device is powered from 2000mAh li-Ion batterry. Capacity is big, but it's selected to main functionality, ANT will be additional feature. Nodes are powered from CR2032 and transmitting broadcast message every 500ms. Separate channels seems to be OK, especially if it will be only 4 nodes. But maybe I'm wrong. I wonder is there power consumption advantage of shared channels?