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AR# 16024

9.1i Schematic - I cannot select symbols at the bottom of the symbol list (symbol list might appear to "flicker")


When I select a category in ECS that has many symbols, and I scroll down, the symbols section begins to flicker once I release the mouse button; it then jumps back to the top of the list. This prevents me from choosing a symbol towards the bottom of the list unless I use a filter.


The "flicker" effect is linked to the refresh operation and the automated check for out-of-date user-created symbols. The flicker problem is machine-dependent and can be fixed by turning off "Check Obsolete Symbol" as follows:

1. Open ECS and select Edit -> Preferences.

2a. Select Schematic Editor in the left tree and make sure "Check Obsolete Symbol Instances" is unchecked in the right pane.

2b. Alternatively, the problem can be fixed by increasing the period of the automatic symbol check (usually by 10 to 100 times the current period).

3. Click OK.

4. If the problem persists, re-start ECS.

In some cases, this problem occurs when the schematic design file is corrupted.

If the problem occurs in some schematics but does not occur in other schematics (Use File -> New -> Schematic to test), use the following procedure to clean up a corrupted schematic file:

1. Make a backup of the project before making any changes!

2. Copy the contents of schematic (Edit -> Select All, Edit -> Copy).

3. Create a new Schematic sheet (File -> New -> Schematic).

4. Paste the schematic content into the new sheet (Edit -> Paste).

5. Delete (or rename) the old schematic.

6. Rename the new schematic sheet to the original schematic name.
AR# 16024
Date Created 09/03/2007
Last Updated 09/27/2011
Status Archive
Type General Article