![](http://datasheet.mmic.net.cn/390000/SAA7120H_datasheet_16832288/SAA7120H_17.png)
2002 Oct 11
17
Philips Semiconductors
Product specification
Digital video encoder
SAA7120H; SAA7121H
Table 21
Subaddresses 63H to 66H (four bytes to program subcarrier frequency)
Note
1.
Examples:
a) NTSC-M: f
sc
= 227.5, f
llc
= 1716
→
FSC = 569408543 (21F07C1FH).
b) PAL-B/G: f
sc
= 283.7516, f
llc
= 1728
→
FSC = 705268427 (2A098ACBH).
Table 22
Subaddresses 67H to 6AH
Table 23
Subaddress 6BH
DATA BYTE
DESCRIPTION
CONDITIONS
REMARKS
FSC0 to
FSC3
f
sc
= subcarrier frequency (in
multiples of line frequency);
f
llc
= clock frequency (in
multiples of line frequency)
note 1
FSC3 = most significant byte;
FSC0 = least significant byte
DATA BYTE
DESCRIPTION
REMARKS
L21O0
L21O1
L21E0
L21E1
first byte of captioning data, odd field
second byte of captioning data, odd field
first byte of extended data, even field
second byte of extended data, even field
LSBs of the respective bytes are encoded
immediately after run-in and framing code, the
MSBs of the respective bytes have to carry the
parity bit, in accordance with the definition of
line 21 encoding format
DATA BYTE
LOGIC
LEVEL
DESCRIPTION
PRCV2
0
polarity of RCV2 as output is active HIGH, rising edge is taken when input, respectively;
default after reset
polarity of RCV2 as output is active LOW, falling edge is taken when input, respectively
pin RCV2 is switched to input; default after reset
pin RCV2 is switched to output
if ORCV2 = HIGH, pin RCV2 provides an HREF signal (horizontal reference pulse that is
defined by RCV2S and RCV2E, also during vertical blanking interval); default after reset
1
0
1
0
ORCV2
CBLF
if ORCV2 = LOW and bit SYMP = LOW, signal input to RCV2 is used for horizontal
synchronization only (if TRCV2 = 1); default after reset
if ORCV2 = HIGH, pin RCV2 provides a ‘composite-blanking-not’ signal, for example a
reference pulse that is defined by RCV2S and RCV2E, excluding vertical blanking interval,
which is defined by FAL and LAL
1
if ORCV2 = LOW and bit SYMP = LOW, signal input to RCV2 is used for horizontal
synchronization (if TRCV2 = 1) and as an internal blanking signal
polarity of RCV1 as output is active HIGH, rising edge is taken when input; default after reset
polarity of RCV1 as output is active LOW, falling edge is taken when input
pin RCV1 is switched to input; default after reset
pin RCV1 is switched to output
horizontal synchronization is taken from RCV1 port (at bit SYMP = LOW) or from decoded
frame sync of “CCIR 656”input (at bit SYMP = HIGH); default after reset
horizontal synchronization is taken from RCV2 port (at bit SYMP = LOW)
defines signal type on pin RCV1; see Table 24
PRCV1
0
1
0
1
0
ORCV1
TRCV2
1
SRCV1
FSC
round
f
llc
f
2
32
×
;
=