SAA7115HLBE NXP Semiconductors, SAA7115HLBE Datasheet - Page 124

• Manufacturer Part Number: SAA7115HLBE
• Description: Video ICs ADV DGTL VIDEO DECODR
• Manufacturer: NXP Semiconductors

Specifications of SAA7115HLBE

• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 70 C
• Package / Case: SOT-407
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Number Of Channels: 2
• Resolution: 8 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: SAA7115HL/V1,557 SAF7115HLBE

PNX1300/01/02/11 Data Book
blending levels from 0 to 0x7F. The MSB is used to turn
on blending (MSB = ‘0’) or to select the overlay plane as
the only output (MSB = ‘1’), so all values between 0x80
and 0xFF select 100% overlay. Therefore, the total num-
ber of blending levels is 129: 128 variable blending val-
ues from 0 to 0x7F plus one ‘blending’ value from 0x80
7.15.2
If the EVO_ENABLE and KEY_ENABLE bits are set to
‘1’ in EVO_CTL the PNX1300 activates chroma keying.
The graphics overlay is taken from a pixel-packed YUV
4:2:2+α data structure in memory. The EVO_KEY regis-
ter provides the value which signifies full transparency
for the overlay. The overlay values (Y, U and V) are com-
pared to the values stored in bit-fields of the EVO_KEY
register. EVO_KEY has three 8-bit fields: KEY_Y,
KEY_U and KEY_V, which store the values to be com-
pared to the Y, U, and V components, respectively, of the
overlay for chroma keying. Bits that correspond to bits
set in MASK_Y and MASK_UV are ignored for the com-
parison. When there is an exact match between the pixel
value and the value in EVO_KEY (disregarding any bits
masked by MASK_Y and MASK_UV), then the overlay
value is not present in the output stream, resulting in full
transparency.
The mask bits in EVO_MASK provide for varying de-
grees of precision in the chroma-key matching process.
The EVO_MASK. MASK_Y field can mask from 0 to 4
LSBs of the overlay Y component during the chroma key
process. For example, setting MASK_Y = 1 eliminates
the influence of the LSB of KEY_Y in the keying process.
This can be used to widen the range of key matching to
account for irregularities in the chroma-key video signal.
Likewise, EVO_MASK. MASK_UV is used to mask from
zero to four LSBs of the overlay U and V components
during the chroma key process. For example, setting
MASK_UV = 1 eliminates the influence of the LSB of
KEY_U and KEY_V in the keying process.
7.15.3
If EVO_CTL. CLIPPING_ENABLE = 1 the EVO performs
fully-compliant programmable clipping. Clipping is per-
formed as the last step of the video pipeline, after chroma
keying and alpha blending. It is applied only on the image
areas (Field 1 and Field 2) defined by IMAGE_WIDTH,
IMAGE_HEIGHT, IMAGE_VOFF and IMAGE_HOFF in-
side the Active Video Area. Blanking values are not
clipped.
The EVO_CLIP MMIO register stores four 8-bit fields
used to clip output components. The Y output compo-
7-14
if alpha[7] = 1 then
else
(or)
Programmable Clipping
Chroma Keying
output[7:0] = overlay[7:0]
output[7:0] = (alpha[6:0] · overlay[7:0] + (alpha[6:0] + 1) · image[7:0]) >> 7
output[7:0] = (alpha[6:0] · (overlay[7:0] – image[7:0]) >> 7) + image[7:0]
PRELIMINARY SPECIFICATION
to 0xFF for 100% overlay. An alpha value of 0 selects
100% image plane and 0% overlay. Similarly, a value of
0x40 selects 50% image and 50% overlay blending.
The equations for the blending are illustrated below.
nent
LOWER_CLIPY and HIGHER_CLIPY. A value less than
or equal to LOWER_CLIPY is forced to LOWER_CLIPY
and a value greater than or equal to HIGHER_CLIPY is
forced to HIGHER_CLIPY.
The same behavior is implemented for U and V with the
values
HIGHER_CLIPUV fields.
This mode allows fully-compliant 16 to 235 Y clipping
and 16 to 240 Cb and Cr clipping to be programmed.
These are the default values of the EVO_CLIP register
after reset.
If CLIPPING_ENABLE = 0, the EVO clips Y, U and V be-
tween the default values 16 and 240, as it is implemented
in the TM-1000. When LOWER_CLIP{Y,UV} registers
are set to ‘0’ and HIGHER_CLIP{Y,UV} registers are set
to ‘255’, no clipping is performed.
7.16
The MMIO registers are in two groups:
• VO registers — control basic VO functions (those
• EVO registers — control new EVO unit functions
VO MMIO registers are shown in
register names are prefixed with “VO_”. Generally, their
functionality is unchanged except where noted in the text
(see for instance,
described in
are discussed in sections
EVO MMIO registers are shown in
MMIO register names are prefixed with “EVO_”. The
EVO_CTL register selectively enables new TM-
1100/TM-1300/PNX1300 functions. The register fields
are described in
cussed in sections
To ensure compatibility with future devices, any unde-
fined MMIO bits should be ignored when read, and writ-
ten as ‘0’s.
shared with the TM-1000 VO unit)
(those new in TM-1100/TM-1300/PNX1300)
is
MMIO REGISTERS
stored
clipped between the
Table
Table 7-9
Section
7.16.4
in
7-6,
Table 7-7
the
7.16.1
7.16.1). The register fields are
and 7.16.5.
and
Philips Semiconductors
Table
LOWER_CLIPUV
through 7.18.1.
Figure
and
values
7-10. They are dis-
Figure
Table
7-29. VO MMIO
7-30. EVO
stored in
7-8. They
and