How can i use negedge of the clock in dspbuilder?

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When I use dspbuilder I don't care how it implements the design as the code is machine code and it is not meant to be edited but used straight away.

The tool takes care of timing. So in short you don't need this clock edge choice. If it does not meet timing then one way is to add registers manually or redesign or increase clock margin.

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WOW,the dspbuilder is so smart ! I am very appreciate for your guide.Your answer solved my confusion.Thank you very much!