How to specify 'destGroups' parameter in mcastSerial function?

[DavidGenge]

There are now two identical robots each with RF200P81 modules. I want to have my remote control unit send the same movement command messages to both units at the same time using mcastSerial(destGroups, ttl). How does one specify 'destGroups'?

Thanks,
Dave
p.s I tried calling ucastSerial() sequentially passing the different target addresses but only one of the robots would respond.

[DavidGenge]

Found Answer under mcastRpc

From the SNAP Ref Manual

"Parameter group specifies which nodes should respond to the request. By default, all nodes belong to the “broadcast” group, group 0x0001. You can configure your nodes to belong to different or additional groups, refer to NV parameter #5 and NV parameter #6 in section 8 on Node Configuration Parameters."

I simply put "mcastSerial(1,1)" in the remote control modules STARTUP and now the robots are dancing in synch!

[Jheath]

You got it.

Just keep in mind that the mcast group parameters are bit maps so a value of "3" or "0x03" is actually membership in group 1 and 2.

3 = 0x03 hex = 0011 binary