This parameter is used to pass the name of the VTS-TSR to the VS command. Names shorter than 8 characters must be blank-filled.
With Release 6.1.1 and above, a VTS-TSR name can be up to 8 characters. Previous releases supported only 4-character VTS names. For compatibility with existing 4-character VTS names, if the last 4 characters of an 8-character VTS name are low-values (binary zeroes), they will be ignored when determining which VTS-TSR to access.