AK8825 Datasheet, PDF (113/162 Pages) Asahi Kasei Microsystems – HD/SD Multi Format Video Encoder with 3ch DAC

■ Video Interface Timing (Composite Video Encoder Block)
[AK8825]
To synchronize with input data, AK8825 supports two kinds of interface mode.
(1) ITU-R BT.656 interface mode
(2) Slave operation with HD/VD Interface mode
This interface mode is set by REC656-bit of SD Blanking Set Register (R/W) [Sub Address 0x10].
SD Blanking Set Register
Sub Address 0x10
bit 7
bit 6
SDBLN4
SDBLN3
bit 5
SDBLN2
bit 4
SDBLN1
bit 3
SDBLN0
bit 2
Reserved
Default Value 0xA1
bit 1
bit 0
Reserved
REC656
REC656-bit
0
1
Interface mode
Slave operation with HD/VD
ITU-R.BT656 I/F mode
Note
(1) ITU-R BT.656 I/F mode
When AK8825 receives ITU-R BT. 656 signal, AK8825 decodes [EAV] code in the data for synchronization then outputs the
HSYNC. AK8825 outputs HSYNC at the rising edge of SYSCLK in the timing of the 32nd/24th (NTSC/PAL) data slot, which is
counted from the [EAV] starting point as below.
REC656-bit=1 of SD Blanking Set Register (R/W) [Sub Address 0x10] should be “0” for setting to this mode.
EAV
Y/Cb/Cr Cb Y Cr Y Cb Y Cr Y
Data#
525 system
360
720
360
721
361
722
361
723
Data#
625 system
360
720
360
721
361
722
361
723
CLKIN
33 / 25T (525 / 625)
HDI
Cb Y Cr
368 736 368
366 732 366
SAV
Y Cb Y Cr Y Cb Y Cr Y Cb
855 428 856 428 857 0 0 0 1 1
861 431 862 431 863 0 0 0 1 1
276/ 288T (525 / 625)
243 / 263T (525 / 625)
Analog Out
Fig. 155
Rev-E-00
113
2008/03