2004 Mar 16
83
Philips Semiconductors
Product specification
PC-CODEC
SAA7108E; SAA7109E
Table 43
Vertical phase offset usage; assignment of the phase offsets
Notes
1.
Case 1: OFIDC[90H[6]] = 0; scaler input field ID as output ID; back-end interprets output field ID at logic 0 as upper
output lines.
Case 2: OFIDC[90H[6]] = 1; task status bit as output ID; back-end interprets output field ID at logic 0 as upper output
lines.
Case 3: OFIDC[90H[6]] = 1; task status bit as output ID; back-end interprets output field ID at logic 1 as upper output
lines.
2.
3.
DETECTED INPUT
FIELD ID
TASK STATUS BIT
VERTICAL PHASE
OFFSET
CASE
EQUATION TO BE USED
0 = upper lines
0
YPY0[7:0] and
YPC0[7:0]
case 1
(1)
case 2
(2)
case 3
(3)
case 1
case 2
case 3
case 1
UP-UP (PHO)
UP-UP
UP-LO
UP-UP (PHO)
UP-LO
UP-UP
0 = upper lines
1
YPY1[7:0] and
YPC1[7:0]
1 = lower lines
0
YPY2[7:0] and
YPC2[7:0]
LO-LO
case 2
case 3
case 1
LO-UP
LO-LO
1 = lower lines
1
YPY3[7:0] and
YPC3[7:0]
LO-LO
case 2
case 3
LO-LO
LO-UP
PHO
64
YSCY[15:0]
16
–
+
PHO
YSC64
16
–
+
9.4
VBI data decoder and capture
(subaddresses 40H to 7FH)
The SAA7108E; SAA7109E contains a versatile VBI data
decoder.
The implementation and programming model accords to
the VBI data slicer the built-in multimedia video data
acquisition circuit of the SAA5284.
The circuitry recovers the actual clock phase during the
clock run-in period, slices the data bits with the selected
data rate, and groups them into bytes. The result is
buffered into a dedicated VBI data FIFO with a capacity of
2
×
56 bytes (2
×
14 Dwords). The clock frequency, signal
source, field frequency and accepted error count must be
defined in subaddress 40H.
The VBI data standards that are supported are given in
Table 44.
For lines 2 to 24 of a field, per VBI line, 1 of 16 standards
can be selected (LCRxxx[41:57[7:0]]: 23
×
2
×
4-bit
programming bits). The definition for line 24 is valid for the
restofthecorresponding field,normally notextdata(video
data) should be selected there (LCR24 = FFH) to stop the
activity of the VBI data slicer during active video.
To adjust the slicers processing to the input signal source,
there are offsets in the horizontal and vertical direction
available (parameters HOFF[5B,59[2:0,7:0]],
VOFF[5B,5A[4,7:0]] and FOFF[5B[7]]).
In difference to the scalers counting, the slicers offsets
define the position of the horizontal and vertical trigger
events related to the processed video field. The trigger
events are the falling edge of HREF and the falling edge of
V123 from the decoder processing part.
The relationship of these programming values to the input
signal and the recommended values can be seen in
Tables 34 to 37.