saa5647hl NXP Semiconductors, saa5647hl Datasheet - Page 84

• Manufacturer Part Number: saa5647hl
• Description: Saa56xx Enhanced Tv Microcontrollers With On-screen Display Osd
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Table 35 TXT display control bits
23.7
Screen colour is displayed from 10.5 to 62.5 ms after the
active edge of the HSYNC input, on TV lines 23 to 310
inclusive for a 625-line display, and on TV lines 17 to 260
inclusive for a 525-line display.
CC: The screen colour is defined by the MMR Display
Control and points to a location in the CLUT table. The
screen colour covers the full video width. It is visible when
the Full Text or Mixed Screen Colour mode is set and no
foreground or background pixels are being displayed.
TXT: Register bits TXT17.SCREEN COL<2:0> can be
used to define a colour to be displayed instead of
TV picture and the black background colour. If the bits are
all set to zero, the screen colour is defined as ‘transparent’,
and TV picture and background colour are displayed as
normal. Otherwise, the bits define CLUT entries 9 to 15.
In double window mode, TXT17.SCREEN COL<2:0>
applies to Text Area A and TXT27.SCRB<2:0> applies to
Text Area B.
23.8
23.8.1
Two types of areas are possible. The one area is static and
the other is dynamic. The dynamic area allows scrolling of
a region to take place. The areas cannot cross each other.
Only one scroll region is possible.
2004 Sep 03
Enhanced TV microcontrollers with
On-Screen Display (OSD)
PICTURE ON
Screen colour
Text display controls
T
EXT DISPLAY CONFIGURATION
0
0
0
1
1
1
TEXT ON
0
1
1
0
1
1
(CC
MODE
BACKGROUND ON
)
X
X
0
1
0
1
84
23.8.2
The display map (see Fig.36) allows a flexible allocation of
data in the memory to individual rows.
Sixteen words are provided in the Display memory for this
purpose. The lower ten bits address the first word in the
memory where the row data starts. This value is an offset
in terms of 16-bit words from the start of Display memory
(8000H). The most significant bit enables the display when
not within the scroll (dynamic) area (see Table 36).
The display memory map is fixed at the first 16 words in
the Closed Caption Display memory.
Table 36 Display map bit allocation
9 to 0
BIT
11
10
Text mode, black screen
Text mode, background always black
Text mode
Video mode
Mixed text and TV mode
Text mode, TV picture outside text area
D
ISPLAY MAP
Text display enable, valid outside Soft Scroll
Area. 0 = disable; 1 = enable.
This bit is reserved, should be set to logic 0.
Pointer to row data.
EFFECT
FUNCTION
Product specification
SAA56xx