From the KNX system point of view, in the start-up process of the gateway and also after a detection of a KNX bus reset, the gateway polls the KNX signals configured to be updated in this situation and maintain the received values in memory to be served to the Modbus system when requested. Also listen for any KNX telegram related to the internal points configured in it and acts accordingly to the configuration of the related point.
From the Modbus system point of view, after the start up process, the gateway listen for any read or write request, and serves any read request or performs any writing request of its internal points received from Modbus system. The values received from Modbus become available to be read by the KNX system and vice-versa.
