V1/man/man5/bppt.5

        11/3/71                                                      BPPT (V)


NAME              binary punched paper tape format

SYNOPSIS

DESCRIPTION       Binary paper tape. is used to pass and store arbitrary
                  information on paper tape. The format chosen has the
                  following features: a) no format of the data is assumed. b)
                  check summing c) zero suppress ion

                  The format is as follows:

                  Between records, NULL characters are ignored. The beginning
                  of the tape is considered between records, thus the leader
                  is ignored.

                  The first non--null character specifies the type and size of
                  the record. If the character is positive (1 to 177), the
                  record is a data record consisting of that many characters.
                  All but the last of these characters are data, the last
                  being a checksum. The checksum is calculated such that the
                  sum of the entire record is zero mod 256.

                  If the first character is negative (200--376) the record is
                  a zero suppression record. It is identical to minus that
                  number of zeros of data. One character of checksum follows
                  this negative character. It is the positive of the negative
                  character.

                  The special case of a record looking like a single zero
                  character suppressed (377;1) causes no data transfer, but
                  is an end--of--file indication.

FILES

SEE ALSO          lbppt, dbppt

DIAGNOSTICS

BUGS

OWNER             ken, dmr