Dear Masazumi,
The simulation time 't' in Simulink ist time the programm has elapsed (inside the system) during the execusion. Therefore (from definition) an offset can not be given. (Here I do not mean the physical time that has ellapsed)
It is possible that the scope has reached an overflow of data in its buffer . If you double click on your scope and you click on the tab 'History' you can increase the number of data points that the scope can display. In the tab 'General' you can define a certain time range if nessesary. Also you could use a 'To Workspace' block or 'To File' block to save the data in the workspace and plot afterwards.
If you like to enable a subsystem in simulink, you can use a 'Enables Subsystem' block, to only calculate the values inside the block when a certain condition is high. For example you could use a 'clock' and an 'compare to constant' to enable this subsystem at a certain time.
Good luck! Christiaan
