
See
NTSC two-~rame sequence,
on
page 512, and
PAL ~our-~rame
sequence,
on page 529.
Bits
FR 1 , FR o,
and F encode field and frame informa-
tion. The F bit functions identically to the F bit of the
4:2:2 interface: It is negated (zero) during the first field,
and asserted during the second field. In NTSC,
FR 1
is
fixed at 0;
FR O
is zero during colorframe A, and asserted
during colorframe B. In PAL,
FR 1
and
FR O
are encoded
00, 01, 10, and 11 to indicate PAL colorframes I, II, III,
and IV, respectively.
If the set {X 4,
X3, X2, X1, Xo, FR 1 , FR 0, F}
contains an
odd number of 1-bits, ...