Roco and Fleischmann Z21 Manuel D'utilisation page 46

Model Railway Control Unit
Example 3: The signal decoder is configured to address 5, and the standard signal configuration (Signal-ID=71 "Universal") is set.
Now send the switching command 2G in order to display "Proceed with 40 km/h" on the first signal. The second turnout number which
is assigned to the signal is 6.
This procedure can also be used in the Z21 App.
Example 4: The signal decoder is configured to address 1, and the standard signal configuration (Signal-ID=71 "Universal") is set.
Configure the signal in the Z21 App as shown in order to switch the appropriate signal aspects with the commands 1R, 1G, 2R or 2G.
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