Forward&Back annotation
When the schematic file and the board file are both open, Forward&Back Annotation automatically links the them so that changes in one file are automatically executed in the other.
For example, if you place a new component, the associated housing appears on the layout at the edge of the board. If you place a net, the signal lines are simultaneously drawn in the layout.
Important: Both the schematic and the board files must always be open at the same time, otherwise the Forward&Back Annotation cannot work and the files fall out of sync.
Certain operations such as the placement or deletion of signals are only allowed in the schematic. Other operations, such as renaming components or changing their values, can be made in in either file.
Note: If you edit one file while the other is closed, when you open both files the Electrical Rule Check (ERC) checks the files for consistency and provides appropriate warnings when inconsistencies are found.