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Filename:
SAA7115_Datasheet.fm
Confidential - NDA required
page 97
Last edited by H. Lambers
Philips Semiconductors
CS-PD Hamburg
CVIP2
Datasheet
SAA7115
Date:
10/23/01
Version:
0.67
For pin constrained applications, or interfaces, the relevant timing and data reference signals can also be encoded into
the data stream. Therefore the corresponding signal pins do not need to be connected. The minimum image port
configuration requires 9 pins only, i.e. 8 pins for data including codes, and 1 pin for clock or gated clock. The inserted
codes are defined in close relationship to the ITU-R BT.656 (D1) recommendation, where possible.
In the case of scaling and for CMOD [80[7]] = ‘0’, the following deviations from “ITU 656 recommendation”are
implemented at the SAA7115s image port interface:
samples, no codes for empty lines (=lines not covered by the scalers window definition)
There may be more or less than 720 pixels between SAV and EAV depending on the scaler settings
Data content and the number of clock cycles during horizontal and vertical blanking is undefined, and may not be
constant. To get a regular pattern in case of scaling, the internal trigger positions for data packing (see section 8.5.4.2.)
need to be balanced.
Data stream may be interleaved with not-valid data, 00H codes or old data (see bit INS80 [93[6]]), but SAV and EAV
4-byte codes are not interleaved with not-valid data codes
There may be an irregular pattern of not-valid data, or IDQ, and as a result, C
B
-Y-C
R
-Y is not in a fixed phase to a
regular clock divider
VBI raw sample streams are enveloped with SAV and EAV, like normal video
Decoded VBI-data is transported as Ancillary (ANC) data or enveloped with SAV and EAV (see bits SLDOM [5D[4:0]]),
two modes:
– direct decoded VBI-data bytes (8-bit), 00H and FFH codes may appear in the data block (violation to ITU-R BT.656)
– recoded VBI-data bytes (8-bit), 00H and FFH codes will be recoded to even parity codes 03H and FCH to suppress
invalid ITU-R BT.656 codes.
Sliced VBI data are transferred as continuous packages with no empty cycles.
The data codes 00H and FFH are suppressed (changed to 01H or FEH respectively) in the active video stream, as well
as in the VBI raw sample stream (VBI pass-through). Optionally, the number range can be further limited
(see bit ILLV [85[5]]).
If the video data are not packed and ITRDY = ‘1’, due to the internal 32 bit wide backend FIFO, valid data occur as 4 byte
(8 bit output), respec. 2 byte (16 bit output) packages of valid data.