User's Manual

UNIVAC SDF TAPE FORMAT
XEROX LASER PRINTING SYSTEMS TAPE FORMATS MANUAL 11-3
The Univac labeled SDF formats offer single and multi-file options on
single and multi-volume tapes. The formats of these options are
shown in figure 11-1.
Univac also produces a labeled ANSI tape format that conforms to
the standard ANSI format for both single- and multi-file, single-
volume formats as shown in figure 11-2. However, the multi-volume
format differs as shown in figure 11-2.
EOT reflector An additional data file is appended following the EOT reflector. The
presence of the EOT reflector is necessary for proper processing of
the multi-volume tape, since the coincidence of the EOT reflector and
the tape mark that terminates a volume spanning file is the signal that
the volume transition is required. The normal SDF format, including
the label control block, is present within the data.
Control and data records Within a file, there are two basic record types: control records and
data records. Control records are identified by the first bit in the
record (bit 35) being set. The control record format is shown in table
11-3; the only control codes supported are shown in this table.
Table 11-2. Fieldata translation table