There are two ways..
1). In Assignments->Settings-> Under "Anaylsis & Synthesis Settings", there's a "Default Parameters". Click on that, then you can enter the parameter name and default setting. In my case, I can add "x" and a default value of "63" for example. This default value will be used everywhere parameter named "x" is used, providing that no other value is assigned to it at a specific block.
2). The draw back for 1) is it's not visualizable on the top level schematic entry design file. It would be tricky for other people to see where "x" takes its value...The second way is that on the top level schematic entry design file, for each block used parameter "x", assigned a value "x_value" to "x". x_value should be defined to have the proper type (integer or binary etc)..Then add PARAM primitives and define "x_value" and assign a specifc value for example "63".
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Care to share how it is done?
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