CCS/CC2652R: Network join surrounded by multiple ZCRs.

Hi,

user6190048 said:

1) When ZR / ZED with PANID 0xFFFF attempts to join the network, ZR/ZED will join which network(ZCR)?

Beacon frames from the various networks are passed up from the NWK Layer to the ZDO layer via ZDO_beaconNotifyIndCB(), the NLME_beaconInd_t function parameter has information like the LQI, router depth, etc. which are used in the decision making.

First the LQI is checked to see if it is greater than the minimum value (gMIN_TREE_LQI) and if the network is open for joining. For each new incoming beacon, the LQI is compared to that of the previous (assuming that there is more than one available network). If the LQI is better on the new beacon than the previous then it will select the network associated to the beacon with the better LQI.

In the case where two networks have the same LQI, it also checks the router depth of the router node and if it is less than the previously selected parent.

Router depth is the number of hops away from the coordinator.

user6190048 said:

2) What are the procedures or variables that determine whether ZR / ZED will join the network?

For more details about the joining procedure please refer to: Network Steering Procedure for a Node not on a Network 

As far as specific criteria for determining possible networks to join: the network must be open (Permit Joining enabled) and have an LQI value greater than the minimum LQI value specified (gMIN_TREE_LQI). This value can be changed in nwk_globals.c (it's default is MIN_LQI_COST_3).

This is assuming that the network is not part of a blacklist, otherwise it will not attempt to join that network, and that it has the correct PAN ID (if one has been specified).

user6190048 said:

3) Does ZCR have variables to control devices that want to join the network?
For example, RSSI(LQI), radius and mac range, etc.

The ZC/ZR does not have variables such as RSSI/ LQI/ Radius and MAC Range that can be used to prevent devices from joining its network.

Best Regards,

Marlyn