Digi SX - One way (unidirectional) PtMP

Question

I have a preconfigured pair of Digi SX radios for my RTK correction signal, a base/master and rover/slave. I'd like to add more rovers so I have cloned the configured rover's settings to the new rover and it works, data sent on any device is recieved by all the others. Now, I don't need the rovers to transmit any data, only receive from the base and in fact I'd prefer it that way in so that no rover could accidentally inject data and corrupt the data stream from the base. I have looked through the xctu and SX user manuals but I have not found any discussion on such a setting, it's probably starring me in the face. Is my idea possible?

Answer 1

Upon further study of the base & rover's configuration in xctu, they appear identical. Is there no set "master" radio in a PtMP setup? I'm running firmware 9007, hardware series A00, device identifier F0000. I'm also wanting to replace my SX (20mW) with a SX PRO (1W) for my base radio and I don't want to miss something when migrating the configuration.

Answer 2

I've ended up setting the rovers to the lowest possible transmit power and setting a destination address of 0 so that if they do transmit all the other radios will ignore the data. The base is still set to use a destination address of 0xFFFF (broadcast).

Answer 3

Your best option would be to use the AG parameter.
https://www.digi.com/resources/documentation/Digidocs/90001477/Default.htm#reference/r_cmd_ag.htm?Highlight=aggregate

You would use AT commands in the console and it would look something like this (assuming the DH and DL of all remote radios are set to default)

+++ (do not hit enter) (you receive OK)
ATAG FFFF [enter] (you receive OK)
ATCN [enter]

This will then send out a remote command to all nodes on the network that will change their DH and DL to point to the SH and SL of the radio on which you enter this command.

For your setup, enter this command on the master and this will cause all remote radios to "talk" to only the master and not to each other.

The other option you have is the manually set each DH and DL of the remote radios with the SH and SL of the master.

It sounds like you currently are using broadcast addressing (everyone hears everything).