“The timing for RX after TX in slaves/meters is given in the standard. EN13757-4. And these timings are all handled in the module!
You can wake the module up from sleep to RX, and the master will expect a TX first from slave. This is how the master can know when the 10 ms window is.
This is the reason why wireless M-Bus is built after the principle that the meter/slave always initiate the communication.
Our master have a patented mailbox system. It can store message to different slaves.
In order for the slave to receive these, the slave MUST send a short “”dummy”” message each 10 minutes and the modules will then automatically
transfer the waiting message in master mailbox. The “”dummy”” message from slave is the only way to let the master know the RX-window is open, even if no transmission is .
needed for other purposes.”

Last Update: January 18, 2018