Project Options - Connection Matrix

Now reading version 16.0. For the latest, read: Project Options - Connection Matrix for version 21

The Connection Matrix tab of the Project Options dialog

The Connection Matrix tab of the Project Options dialog


This tab of the Project Options dialog delivers a matrix providing a mechanism to establish connectivity rules between component pins and net identifiers, such as Ports and Sheet Entries. It defines the logical or electrical conditions that are to be reported as warnings or errors. For example, an output pin connected to another output pin would normally be regarded as an error condition, but two connected passive pins would not.

When the project is compiled, these violation settings will be used - in conjunction with the defined settings on the Error Reporting tab - to test the source documents for violations. Any violations that are found and have a report level of Warning, Error, or Fatal Error will be displayed as violation messages in the Messages panel. In addition, if compiler errors and warnings are enabled for display on the schematic (enabled on the Schematic - Compiler page of the Preferences dialog), an offending object will display a colored squiggle beneath it.

The process of compiling is integral to producing a valid netlist for a project. In fact it is the process of compilation that yields the unified data model of a design. Carefully check and resolve all reported errors prior to netlist generation.
For a comprehensive reference describing each of the possible electrical and drafting violations that can exist on source documents when compiling a project, refer to the Project Compiler Violations Reference.


This is one of multiple tabs available when configuring the options for a project accessed from within the Project Options dialog. To access this dialog:

  • Click Project » Project Options in the Schematic or PCB Editor.
  • Right-click on the Project entry on the Projects panel then click Project Options from the context menu.


Connection Matrix

The matrix presents all possible wiring connection checks, between combinations of pins, ports, and sheet entries, as well as testing for unconnected entities. The matrix is read in an across/down fashion and the color of the matrix element at the row-column intersection specifies how the Compiler will respond when testing for that particular condition.

To change the reporting mode for a violation check in the matrix, simply click on the colored square where the row and column of two entities intersect. Each time you click, the mode will move to the next report level. The following levels are supported:

As you hover over a square, text is displayed below the matrix to describe the connectivity violation and the reporting mode in force.

Right-Click Menu

The following commands are available from the right-click context menu for the tab:

  • All Off - set all entries in the matrix to No Report.
  • All Warning - set all entries in the matrix to Warning.
  • All Error - set all entries in the matrix to Error.
  • All Fatal - set all entries in the matrix to Fatal.
  • Default - set all entries in the matrix back to their default settings.


  • Use the Project Options - Error Reporting dialog to specify reporting levels associated with further electrical and drafting violations.
  • There may be points in the design that you know will be flagged as electrical violations, which you do not want to be flagged. To suppress these, place a No ERC schematic design directive object at each point.
If you find an issue, select the text/image and pressCtrl + Enterto send us your feedback.

The features available depend on your Altium product access level. If you don’t see a discussed feature in your software, contact Altium Sales to find out more.