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AR# 12666

4.1i ECS - After importing schematic files from 3.1i to 4.1i, DRC errors report "Nets must be connected to pins or I/O Ports" and "Too many source pins".


Keywords: 4.1i, ECS, conversion, symbol

Urgency: Hot

General Description:
After I import a schematic design from 3.1i to 4.1i, ISE reports the following error and warning:

Error: Net <net name> must be connected to pins or I/O Ports.
Warning: Net <net name> is connected to too many source pins. A Wired or connection will be used.


This error occurs when the schematic file is imported from 3.1i to 4.1i. The polarity of the input ports of the user-made symbols is not declared, so it defaults to output.

To eliminate this error, download the following ZIP file:


This ZIP file contains two files that will update the ECS symbols in a project directory. It also contains a readme.txt file that explains their usage.

Alternatively, for small designs with relatively few symbols, you may update each symbol manually by following these steps:

1. Select the nets that were named in the error message.
2. Trace the net to any sub-block and select the sub-block.
3. Right-click on the block and select "Edit Symbol".
4. In the new symbol window, select the symbol.
5. Right-click on the symbol and select "Object Properties".
6. In the Category window, expand the pins and select the input pins.
7. In the Symbol Attribute window, you will notice that no polarity is assigned to the pins.
8. Select all the input pins that do not have polarity assigned.
9. Click New, and enter "Polarity" for attribute name and "IN" for attribute value.
10. Select "OK", save, and update the symbol.

Repeat this process for all the sub-blocks.
AR# 12666
Date Created 09/25/2001
Last Updated 08/11/2003
Status Archive
Type General Article