Multi connection handling

Question

Hi, 
 your Central is able to hold 8 connections with peripherals. Perhaps someone is able to explain how more than one connection is handled? If only one Central is connected to a Peripheral everything is clear to me. But how are 2 or more Peripherals connected to a Central able to exchange data simultaneously?
Thanks!

Petter Myhre · Accepted Answer

Since you mention 8 connections I'm assuming you are talking about the S120 SoftDevice. Multi-link Central role scheduling is explained in Section 11 in S120 SoftDevice specification v2.1. 
 
 In my opinion only one connection can
use the RF interface. 
 
 Only on connection can use the radio at one point in time, so if you have two connections that overlap, the connection event of one of them will be dropped. More information about this in Section 11.4. 
 
 Sometimes both peripherals want to
communicate with the Central at the
same time. 
 
 If a peripheral wants to communicate with the central it has to do this in a connection event, which happends every connection interval. Normally the connection events of two (or more) connected peripherals will not happen at the same time (very often), but this depends on what connection parameters that are used. The more connected peripherals and the tighter connection parameters used the higher is the chance for dropping a connection event. Dropping one event will not normally lead to a connection loss (depends on what the connection parameters), but it can lead to a delay in tranferring data from the peripheral to the central (or the vise versa). 
 
 How is the channel hopping managed? 
 
 There is no problem changing channels, this is done all the time. For example when you are doing advertising, every advertisement is sent on the three advertising channels consecutively.