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AR# 16650

Schematic - An unconnected pin on the startup block causes the error: "$/start/start.vhf",line 31: Error, CLK does not have an actual or default value"


When I use the Virtex-II startup block with the Clk port unconnected, synthesis fails and the following error appears:

"$/start/start.vhf",line 31: Error, CLK does not have an actual or default value."


You can work around this problem in two ways:

1. Assign a default value (:= 'X') to the startup component ports.

2. Add an unconnected net to the CLK port of the startup block.

- Change the "Consider Undriven Nets as" setting in ECS by going to Edit -> Preferences -> Check. Change this setting from "Error" to "Warning".

AR# 16650
Date 12/15/2012
Status Archive
Type General Article