SAA5281 Datasheet, PDF (23/48 Pages) NXP Semiconductors – Integrated Video input processor and Teletext decoder IVT1.8

Philips Semiconductors
Integrated Video input processor and
Teletext decoder (IVT1.8*)
Preliminary specification
SAA5281
REGISTER BIT D0 TO D7
FUNCTION
R4 DISPLAY CHAPTER - auto-increments to Register 5
A0 to A2
Selects one of 8 display chapters.
FREEZE HEADER ONLY
Freezes the rolling header, but (unlike R0D4) allows the time to roll.
R5 NORMAL DISPLAY CONTROL - auto-increments to Register 6
R6 NEWSFLASH/SUBTITLE DISPLAY CONTROL - auto-increments to Register 7; note 1
PON
Picture on.
TEXT
Text on.
COR
Contrast reduction on.
BKGND
Background colour on.
R7 DISPLAY MODE - does not auto-increment
BOX ON 0
Boxing function allowed on Row 0.
BOX ON 1 to 23
Boxing function allowed on Rows1 to 23.
BOX ON 24
Boxing function allowed on Row 24.
SINGLE/DOUBLE HEIGHT
To display double height text.
TOP/BTM HALF
To select bottom half of page when DOUBLE HEIGHT is logic 1.
CONCEAL/REVEAL ON
To reveal concealed text.
CURSOR ON
To display cursor.
STATUS BTM/TOP
Row 25 displayed above or below the main text.
R8 ACTIVE CHAPTER - auto-increments to Register 9
A0 to A2
Active chapter for data written to or read from memory via the I²C-bus.
CLEAR MEM
When set to logic 1, clears the display memory. This bit is automatically reset.
VPS ENABLE
VPS acquisition enabled when logic 1.
R9 CURSOR ROW - auto-increments to Register 10
R0 to R4
Active row for data written to or read from memory via the I²C-bus.
R10 CURSOR COLUMN - auto-increments to Register 11 or 11B
C0 to C5
Active column for data written to or read from memory via the I²C-bus.
R11 CURSOR DATA - does not auto-increment
D0 to D7
Data read from/written to memory via I²C-bus, at location pointed to by R9 and
R10. This location automatically increments each time R11 is accessed.
R11B DEVICE STATUS - does not auto-increment
VCS SIGNAL QUALITY
Indicates that the video signal quality is good and PLL is phase-locked to input
video when logic 1.
TEXT SIGNAL QUALITY
If a good teletext signal is being received then logic 1.
ROM VER R0 to R4
Indicated language/ROM variant. For Western European is logic 0. R3 and R4 are
set HIGH if R13 D6 is logic 1.
625/525 SYNC
If the input video is a 525 line signal then logic 1.
R12 ADVANCED CONTROL 2A - does not auto-increment
S0 to S3, H0 to H3
Each acquisition channel can be programmed to process its page in one of four
ways as shown in Table 12.
1996 Nov 04
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