Question about the BlueNRG-2N Simultaneous Connections

[RrW1]

Hi,

I was reading the BlueNRG-2N features on this datasheet, and it stated that it could "handle up to 8 simultaneous connections."

Does this mean that one GAP Central device based on the BlueNRG-2N could transmit up to 8 GAP Peripheral devices (also containing the BlueNRG-2N) at the exact same timeframe?

In the example above, if I were to transmit the same packet to 8 devices at t1 = x seconds, and if I set a connection length of ConnectionLength = y seconds for all the peripheral devices connected to it, all 8 peripherals would receive the packet at x + y + <some_hardware_overhead> seconds after it was transmitted by the GAP central device? Also, if all the GAP Peripheral devices were to send a message back through an Indicate/Notify operation, the GAP central could also receive all the Indicate/Notify messages from the 8 Peripheral devices at the same time?

Any clarification would be helpful. Thanks!

[Winfred LU]

A BLE connection is made by one master and one slave. The 8 connections will be made by 8 (8 logical / 1 physical) masters and 8 slaves.

In the case connecting with 8 slave devices, the packets to each slave devices need to be sent separately (one on one) in each time slot:

 

Please consider to use beacons if broadcast is needed for the application. Or Use Mesh in case multicast is needed.

[RrW1]

Hi Winfred,

Thank you for the image description of the connections. So basically when the datasheet mentioned that it could handle up to 8 simultaneous connections, the master device (GAP Central) can only be connected to 8 devices at a time (as in having 8 separate connection handles in the GATT layer)? When you mentioned considering using Beacon, are you referring to advertising the packets from one device to the 8 devices at the same time?

Is it also possible for a master device to create connections with 8 slave devices, where the master will be initialized as a GAP Central to allow creating connections with the slaves, and then allow the master device to broadcast as a GAP Broadcaster? I am trying to accomplish broadcasting data to multiple slaves at the same time, while also establishing individual connections with those slave devices as depicted in your diagram above. The reason for this is because I would like data to be transmitted synchronously (arriving at the same time in those 8 slave devices), but I would also like to retrieve data from those 8 slaves individually.

Thanks!