LMH0031 Datasheet, PDF (24/31 Pages) National Semiconductor (TI) – SMPTE 292M/259M Digital Video Deserializer Descrambler with Video and Ancillary Data FIFOs

Device Operation (Continued)
TABLE 5. Test Pattern Selection Codes (Continued)
Test Pattern Select Word Bits >
Bit 5
Bit 4
Bit 3
Bit 2
525 Line, 30 Frame, 27 MHz, NTSC 4x3 (SMPTE 125M)
Ref. Black
0
0
0
0
PLL Path.
0
0
0
0
EQ Path.
0
0
0
0
Colour Bars (SD BIST)
0
0
0
0
625 Line, 25 Frame, 27 MHz, PAL 4x3 (ITU-T BT.601)
Ref. Black
0
1
0
0
PLL Path. (SD BIST)
0
1
0
0
EQ Path.
0
1
0
0
Colour Bars
0
1
0
0
525 Line, 30 Frame, 36 MHz, NTSC 16x9 (SMPTE 125M)
Ref. Black
0
0
0
1
PLL Path.
0
0
0
1
EQ Path.
0
0
0
1
Colour Bars
0
0
0
1
625 Line, 25 Frame, 36 MHz, PAL 16x9 (ITU-T BT.601)
Ref. Black
0
1
0
1
PLL Path.
0
1
0
1
EQ Path.
0
1
0
1
Colour Bars
0
1
0
1
525 Line, 30 Frame, 54 MHz (NTSC)
Ref. Black
0
0
1
0
PLL Path.
0
0
1
0
EQ Path.
0
0
1
0
Colour Bars
0
0
1
0
625 Line, 25 Frame, 54 MHz (PAL)
Ref. Black
0
1
1
0
PLL Path.
0
1
1
0
EQ Path.
0
1
1
0
Colour Bars
0
1
1
0
Note: BIST test patterns for SD are: NTSC 4x3 Colour Bars and PAL 4x3 PLL Pathological.
Bit 1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
Bit 0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
VIDEO INFO 0 REGISTER (Address 0Eh)
Re-synchronization of the parallel video output data with the
parallel rate clock is controlled by the functions Framing
Enable, Framing Mode and NSP. For operating details
about these control bits, refer to the preceeding section
about Format Registers 0 and 1 and the Format Mode bit.
Framing Enable may be assigned as an input on the multi-
function I/O port.
The NSP (New Sync Position) bit indicates that a new or
out-of-place TRS character has been detected in the input
data. This bit is set to a logic-1 and remains set for at least
one horizontal line period or unless re-activated by a subse-
quent new or out-of-place TRS. It is reset by an EAV TRS
character.
The EAV (end of active video) and SAV (start of active video)
bits track the occurrence of the corresponding TRS charac-
ters.
The Lock Detect is a logic-1 when the loop is locked and the
CDR has acquired a phase of the incoming serial data. This
bit may be programmed as an output on the multi-function
I/O bus. This bit is mapped to I/O port bit 4 in the default
condition.
The VPG Filter Enable bit when set enables operation of the
Video Pattern Generator filter. Operation of this filter causes
the insertion of transition codes in the chroma and luma data
of colour bar test patterns where these patterns change from
one bar to the next. This filter reduces the magnitude of
out-of-band frequency products which are produced by
abrupt transitions in the chroma and luma data when fed to
D-to-A converters and picture monitors.
The LMH0031 incorporates circuitry that implements a
method for handling data that has been subjected to LSB
dithering. Data from the de-scrambler is routed for de-
dithering. Control of this circuitry is via the De-Dither Enable
bit in the VIDEO INFO 0 control register. Recovery of data
that has been dithered during the vertical blanking interval
can be selectively enabled by use of the V De-Dither Enable
bit in the VIDEO INFO 0 control register. The initial condition
of De-Dither Enable and V De-Dither Enable is OFF.
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