HMP8117 Datasheet, PDF (17/45 Pages) Intersil Corporation – NTSC/PAL Video Decoder

HMP8117
The WSS odd field Read status bit is always a “0”. The WSS
even field Read status bit is set to “1” after data has been
transferred from the shift register to the WSS_EVEN_A and
WSS_EVEN_B registers. It is set to “0” after the data has
been read out.
ODD AND EVEN WSS
WSS data present on line 20 (or line 17 or 23 in the PAL
modes) is captured into a shift register then transferred to
the WSS_ODD_A and WSS_ODD_B registers. WSS data
present on line 283 (or line 280 or 336 in the PAL modes) is
captured into a shift register then transferred to the
WSS_EVEN_A and WSS_EVEN_B registers.
The WSS odd field Read status bit is set to “1” after data has
been transferred from the shift register to the WSS_ODD_A
and WSS_ODD_B registers. It is set to “0” after the data has
been read out.
The WSS even field Read status bit is set to “1” after data
has been transferred from the shift register to the
WSS_EVEN_A and WSS_EVEN_B registers. It is set to “0”
after the data has been read out.
BT.656 Ancillary Data
Through the BT.656 interface the HMP8117 can generate
non-active video data which contains CC, WSS, teletext or
Real-Time Control Interface (RTCI) information. Teletext and
RTCI data is only available as BT.656 ancillary data.
VBIVALID Output Timing
The VBIVALID output is asserted when outputting Closed
Captioning, Wide Screen Signalling, Teletext or RTCI data
as BT.656 ancillary data. It is asserted during the entire
BT.656 ancillary data packet time, including the preamble.
BT.656 Closed Captioning and Wide Screen
Signalling
Table 6 illustrates the format when outputting the caption
data registers as BT.656 ancillary data. The ancillary data is
present during the horizontal blanking interval after the line
containing the captioning information.
Table 7 illustrates the format when outputting the WSS data
registers as BT.656 ancillary data. The ancillary data is
present during the horizontal blanking interval after the line
containing the WSS information.
CLK
VBIVALID
P[15-8]
00
FF
FF
DATA ID BLK # # BYTES/4 BYTE #1 BYTE #2 BYTE #3 BYTE #4
NOTES:
t_DVLD
23. BT.656 VBI ancillary starts with a 00H, FFH and FFH sequence which is opposite to the SAV/EAV sequence of FFH, 00H and 00H.
24. During active VBI data intervals, DVALID is deasserted and BLANK is asserted.
FIGURE 15. OUTPUT TIMING FOR BT.656 VBI DATA TRANSFERS (CC, WSS, TELETEXT, RTCI)
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