HMP8156ACN Intersil, HMP8156ACN Datasheet - Page 4

• Manufacturer Part Number: HMP8156ACN
• Description: NTSC/PAL Encoder 64-Pin MQFP
• Manufacturer: Intersil

Specifications of HMP8156ACN

• Package: 64MQFP
• Operating Temperature: 0 to 70 °C

Note that overlay capability is not available when the 24-bit
RGB input format is used.
The encoder provides 4 methods for mixing the overlay data
with the pixel data: disabled, external mixing, internal mixing
and no mixing. The method used is selected in the input
format control register.
Overlay Mixing: Disabled
When overlay mixing is disabled, the OL0-OL2, M0, and M1
inputs are ignored and the pixel data is not changed.
Overlay Mixing: External
When external overlay mixing is selected, mixing of overlay
data and pixel data is controlled by the M1 and M0 inputs.
M1 and M0 indicate the mixing level between the pixel inputs
and the overlay inputs, on a pixel-by-pixel basis. M1 and M0
are ignored if OL2-OL0 = 000. Otherwise, they select the
percentage of each color to sum as shown in Table 3.
NAME
PIN
P10
P11
P12
P13
P14
P15
P16
P17
P18
P19
P20
P21
P22
P23
P0
P1
P2
P3
P4
P5
P6
P7
P8
P9
OL2-OL0
TABLE 2. OVERLAY COLOR PALETTE
000
001
010
100
101
011
110
111
Cb0, Cr0
Cb1, Cr1
Cb2, Cr2
Cb3, Cr3
Cb4, Cr4
Cb5, Cr5
Cb6, Cr6
Cb7, Cr7
YCBCR
16-BIT
4:2:2
Y0
Y1
Y2
Y3
Y4
Y5
Y6
Y7
4
75% Magenta
100% White
75% Green
75% Yellow
Y0, Cb0, Cr0
Y1, Cb1, Cr1
Y2, Cb2, Cr2
Y3, Cb3, Cr3
Y4, Cb4, Cr4
Y5, Cb5, Cr5
Y6, Cb6, Cr6
Y7, Cb7, Cr7
75% Cyan
Pixel Data
75% Blue
75% Red
COLOR
YCBCR
8-BIT
4:2:2
TABLE 1. PIXEL DATA INPUT FORMATS
HMP8154, HMP8156A
OL0
OL1
OL2
Ignored
M0
M1
-
-
-
SAV and EAV
YCbCr Data,
Sequences
BT.656
In external mixing mode, there is no minimum number of
pixels an overlay color or pixel color must be selected. The
mixing level may also vary at any rate.
Overlay Mixing: Internal
Mixing of overlay and pixel data may also be controlled
internally, and the M1 and M0 input pins are ignored. A
transition from pixel data to overlays, from overlays to pixel
data, or between different overlay colors triggers the mixing
function. An overlay color must be selected for a minimum of
three pixels for proper overlay operation in this mode. Internal
overlay mixing should not be used with the BT.656 input format.
When going from pixel to overlay data, mixing starts one
pixel before the selection of the overlay color (OL2-OL1 !=
000). The first pixel output before the overlay uses 12.5%
overlay color plus 87.5% pixel color. The next output is
aligned with the selection of the overlay color and uses
87.5% overlay color plus 12.5% pixel color. Additional
outputs use 100% overlay color.
M1, M0
00
01
10
11
TABLE 3. OVERLAY MIXING FACTORS
SCREEN
Ignored
BLUE
% OVERLAY
COLOR
12.5
87.5
100
(5, 6, 5)
16-BIT
0
RGB
G0
G1
G2
G3
G4
G5
R0
R1
R2
R3
R4
B0
B1
B2
B3
B4
% PIXEL
COLOR
24-BIT
RGB
87.5
12.5
100
August 20, 2009
B0
B1
B2
B3
B4
B5
B6
B7
G0
G1
G2
G3
G4
G5
G6
G7
R0
R1
R2
R3
R4
R5
R6
R7
0
FN4343.5