SPRUJ52C june 2022 – july 2023 AM69 , AM69A , TDA4AH-Q1 , TDA4AP-Q1 , TDA4VH-Q1 , TDA4VP-Q1
The End of Active Video (EAV) and Start of Active Video (SAV) parts of the stream are timing codes. Their function can be summarized as follows:
These codes are embedded within the BT.656 video data stream, thereby eliminating the need for additional timing signals (HSYNC, VSYNC) to be included as part of the interface.
Both EAV and SAV codes are comprised of a sequence of four bytes ( FFh – 00h – 00h - XY). The first three bytes in the sequence constitute a fixed preamble. The fourth byte, contains information about the field being transmitted (Field 1 or Field 2 in an interlaced video signal), the state of field blanking (Vertical) and the state of line blanking (Horizontal). The bit assignment for this byte of the code is shown in Figure 12-404, with the function of each bit described inTable 12-425.
Bit | Symbol | Function |
---|---|---|
7 | 1 | Always set to '1'. |
6 | F | Field bit. 0 – Field 1 1 – Field 2 |
5 |