step 1. right click "synthesize", click "open interactively";
step 2. after the "synplify pro L" window appeared, right click "synthesis" under "project files" ,click "new identify implementation"
step 3. in the "add identify impementation" window, set the implementation name, click "ok";
step 4. right click the new implementation created in last step( synthesis_1), click "identify instrumentor";
step 5. choose the signals and sample clock, the sample clock is necessary;
setp 6. click "save",and run the implemention;
step 7. close this window, click "identify debug design", here a long time is needed
step 8. in the identify debugger window,click run,and click another button in the pic follow
step 9. a new window will show the wave contains the signals you want;