What does the "interlock" function do on the DCC-1?

When using the DCC-1, you can select to use the interlock function if you want to "lock" the DCC-1 and the DS module to function together.

Interlock forces the setpoint on the DCC-1 and the DS (Device Station) module to be activated in order for the DS module to be activated.

Leaving the interlock off allows the setpoint on the DCC-1 or the setpoint on the DS module to activate the DS module independently.