le: Set-GR-Trace 1 Set-MSC - Trace System V76test 0 Set-MSC-Trace Process <<Block DLCa>> DLC 2 List-MSC-Trace-Values t-Interactive-MSC-Log 2 Output-To L_EstabReq (0) <<Block DLCa>> dispatch "Yes" "Yes" */ 2 /* "Yes" 14 Conditional means that an entity - for example, a process - will be traced only if it exchanges signals with entities present in the MSC trace. This avoids having entities present in the MSC trace but not exchanging any signal. Interactive Simulation 53 process MSC retry1 <<Block DLCa>> DLC DLC_1_1 Void_2 N320cnt := 0 V76frame ( SABME : (.0.) ) T320(12.00) waitUA N320cnt := 1 V76frame ( SABME : (.0.) ) T320(12.00) waitUA N320cnt V76frame ( SABME : (.0.) ) T320(12.00) waitUA N320cnt := 3 V76frame ( SABME : (.0.) ) T320(12.00) waitUA DLCstopped Void_2 /* DLCstopped never input. */ Figure 4.15 The three SABME retransmissions in the MSC generated by the Simulator 2 /* "Yes" * / Next-Transition Do not exit from the Simulator. 4.2.3.2 Analyze the bug To understand the bug, you will search in which state process dispatch (in block DLCa) was when process DLC transmitted the signal DLCstopped to it. A. In the Simulator, select View > Command Window: the Command Window appears, as shown in Figure 4.7; check the box List-Process: you can see that dispatch in block DLCa is in state waitUA. B. In the Simulator, select Show > Prev Symbol: as shown in Figure 4.16, in process DLC the Editor selects the stop symbol, below the output of DLCstopped, which caused the problem. 54 Validation of Communications Systems with SDL SDL Simulator UI-F:ADONNEES\TRANSMET\livreSimul\modelsSDTW76W76_v1WV76test_smc.exe P SDL Editor Process DLC/part1 F:ADONN File View Buttons Log General Execute Examine Change Irace Breakpoint File Edit View Pages Diagrams Window Tools Help Next Symbol Prev Symbol Execute Group C Line N320ont= Coverage <<Block DLCa>> DLC:1 N320cnt + 1 Symbol Break 48.0000 Transition Until Timer TRANSITION START : <<Block DLCa>> DLC:1 retry Send Signal Group State vaitUA Input Send To Send Via Send None Sender <<Bloc