k DLCa>> DLC:1 : 48.0000 DLCstopped DECISION Value: false Examine Group OUTPUT of DLCstopped to <<Block DLCa (no signals were discarded) Process List Variable Var In Scope Next-Transition No process instance scheduled for a tran Trace Group Command Execute command Show-Previous-Symbol SimUI Command MSC Editor Simulator Trace/1 File Command File Edit View Pages Diagrama Window Tools Help List-Ready-Queue Command The ready queue is empty decision false List-Process Command State Signals Signal DLCstopped env:1 start state Void_2 AtoB:1 ready BtoA:1 ready dispatch:1 waitUA <<Block DLCa>> Figure 4.16 Finding the stop symbol that caused the problem C. In the SDL Editor, select Page > Edit Reference Page: the block type V76_DLC is now displayed, as in Figure 3.12; you see that signal DLCstopped goes to process dispatch, through the signal route DLCs. D. In the SDL Editor, double-click on the process dispatch to open it; press the Next Page button to display part2: you see that under state waitUA, the input of signal DLCstopped is missing. E. Exit from the Simulator. 4.2.3.3 Correct the bug You will add the missing input of signal DLCstopped under state waitUA in process dispatch. A. In Windows (or Unix), make a copy of the file dispatch.spr, containing the process dispatch, into dispatch_vl.spr. Continue editing dispatch.spr. B. In process dispatch, select the input of DLCstopped and the next three symbols under the state ready, copy them, paste them near state waitUA and connect the state to the input as shown in Figure 4.17. Interactive Simulation 55 waitUA V76frame DLCstopped (V76para) (DLCnum) 76para ! present L_ReleaseInd (DLCnum) V76frame(V76para) DLCs(DLCnum) TO DLCs(V76para := NULL !UA!DLCi) ready ready Figure 4.17 Missing DLCstopped input added under state waitUA C. In the pasted transition, don't forget to replace - in the nextstate symbol by ready, otherwise you would be stuck in state waitUA. D. Save the SDL model. 4.2.3.4 Simulate to check the bug correction To check that the bug has been corrected, you wi