Multilink peripheral RAM settings

[Martin Kulessa]

Hi, i try to establish a communication between 3 sensors in the following way!

Node 1 should broadcast messages to Node 2 and Node 3 as Peripheral. To establish a connection now between Node 1 and Node 2, Node 2 acts as central and connects to Node 3 as a seconde peripheral device!

First of all is it possible to use the Multiperipheral on nRF51422 or just on nRF52 series?

Second how do i have to extend the RAM to use a second Peripheral based on ble_nus_uart app peripheral?

[Petter Myhre]

The latest version of the S130 SoftDevice, for the nRF51, does not support multiperipheral, so your suggested topology is not possible.

Node 1 can be connected to Node 2 as a central, and to Node 3 as a peripheral.

Node 2 can be connected to Node 3 as a central, and to Node 1 as a peripheral.

Node 3 can be connected to Node 1 as a central, and to Node 2 as a peripheral.

[binhnguyens]

how would you do it with s132 nrf52 dk?

[Petter Myhre]

S132 4.0.3 supports multiperipheral, so with it you have more options. What topology to use is very application dependent.

[Martin Kulessa]

1. Yes my Problem is also time dependence! Even if there are no guarantees for Bluetooth Low Energie and i could use the generic Radio is there a difference of the broadcast time to be expected when i broadcast from Node1 to a central (Node 3) or from Node 1 to a peripheral (Node2)
2. On nRF52 S132 4.0.3 how do i have to change the applications RAM settings to extend the peripherals from 1 to 2 in the ble_app_uart for example?

[Petter Myhre]

Extending the RAM for the SoftDevice alone doesn't really help, but you do it by chaining RAM start and RAM size in your project settings. You have to modify the example so that it supports two peripheral connections at the same time. We don't really have an official example, but I made an example for S132 4.0.0-2.alpha that might be helpful. You can find it here.