event get value based on the physical address

[Fahd]

Hi, 

I have a 1byte Value group address (10/0/23 ) and there are two KNX devices that are sending  values in that group address  ( their physical address is 8.0.10 and 8.3.3 )

How can I write the same value on another grp address only when 8.0.10 is the one that sends it?