$IV, $INITIAL_SPEED, $STARTSPEED
When a vehicle starts, it begins to move with this speed - and it accelerates according to its acceleration value, either specified in the movement's parameter, or from the default value inherited from the segment hierarchy.
The vehicle can move only a whole pixel. If the initial speed is too low, you will see single 1-pixel wide "jumps" at the beginning of the movement. Conversely, when it is set too high, the vehicle starts to move abruptly as if it were a Formula 1 racing car. Ultimately, this setting should be set to the user's preferences.
Normally, you will want to use the command form to set this parameter; to set the value you find pleasing to the eye one time for the whole timetable file. The default value of one pixel is usually considered acceptable to most people.
The Configuration Window
Configuration Window Menu Bar
Stock List Menu Bar
Graphic Testpad Menu Bar
Timetable Syntax and Semanics
The timetable header
Sections, Groups, Lines, Scenes
Stock List File