Patent ID: 8521925

Claim:
A communication system ( 1 ) comprising: a higher-level controller ( 20 ) including a system clock ( 25 ); and at least one input/output (IO) link device ( 40 ) connected to the higher-level controller ( 20 ), the IO link device having multiple connection devices/ports ( 41 - 44 ) to which in each case a first IO device ( 51 - 53 ) is able to be connected, wherein neither the IO link device ( 40 ) nor the first IO devices ( 51 - 53 ) have a local clock; wherein a second IO device ( 50 ) is connected to one of the connection devices/ports ( 41 ) of the IO link device ( 40 ), the second IO device including a clock, wherein a synchronization device is provided that synchronizes the clock of the second IO device ( 50 ) with the system clock ( 25 ) of the higher-level controller ( 20 ), and wherein the transmission of status data which are provided by at least one of the first IO devices ( 51 - 53 ) and the transmission of current time data which the second IO device ( 50 ) supplies are effected simultaneously to the IO link device ( 40 ), and wherein the IO link device ( 40 ) assigns the status data received from the at least one of the first IO devices to the received current time data and transmits these data to the higher-level controller ( 20 ).