Evaluate the velocity meters of the specified block sections.
At least one block section must be specified by its
label. To simplify typing commands capital letters may be replaced by small letters
and underscores may be omitted.
"trace velocity meters" : RC-> t [<block>]*
Start tracing the velocity meters of the specified block sections. Each time a
train passes one of the selected velocity meters, the measured value is displayed
immediately. The set of selected velocity meters may be changed by issuing
further trace commands. Specifiying an empty set terminates the trace.
At least one block section must be specified by its
label. To simplify typing commands capital letters may be replaced by small letters
and underscores may be omitted.