XST allows different types of instantiations. Below is a list to help instantiate the different types of components that may be encountered in a design:
Please refer to
(Xilinx Answer 39978) for help debugging issues when instantiating custom modules.
Please refer to
(Xilinx Answer 39979) for help debugging issues when instantiating primitives.
Please refer to
(Xilinx Answer 39980) for help debugging issues when instantiating black boxed components.
Please refer to
(Xilinx Answer 39981) for help debugging issues when instantiating Xilinx Cores.