AK8851 Datasheet, PDF (17/80 Pages) Asahi Kasei Microsystems – NTSC/PAL/SECAM Digital Video Decoder

ASAHI KASEI
[AUTODET]-bit:
SET the [AUTODET]-bit in order to automatically distinguish input signals.
[AUTODET]-bit
On/Off
Note
0
OFF
1
ON
Cannot detect with or w/o Setup
(footnote)
following input signal characteristics are automatically detected.
[AK8851]
Number of Lines per each Frame:525/625
Sub-Carrier frequency : 3.58/4.43 MHZ
Color Encoding systems: NTSC/PAL/SECAM
With the automatic distinguishing capability described above, the input signal is verified to be one of the following:
NTSC/NTSC-4.43/PAL-B, D, G, H, I/PAL-M/PAL-N (ARG)/PAL-60/SECAM.
The verification result is stored in [Input Video Status Register][sub Address 0x00].
Automatic verification of the SETUP feature is not performed. The following set-up process is performed while the automatic
verification function is enabled.
Setup Recognition (Default)
Recognized Signal
[Control 2 Register]
Validation of SETUP-bit
[STUPATOFF-bit ] = 0
NTSC
PAL-B,D,G,H,I,N,Nc,60
No setup process
Setup Procedure is done with SETUP-bit is 1
SECAM
PAL-M
NTSC-4.43
Setup process
Setup-bit is disable. The setup procedure is always done.
Please set the [Input Video Standard Register][Sub Address 0x01] [SETUP]-bit when an input signal with values other than
those shown above is input (SETUP process is performed regardless of SETUP-bit status for PAL-M and NTSC-4.43 signal).
The automatic set-up process can be turned off by [STUPATOFF-bit] of the Control2 Register. In this case, use the
SETUP-bit to enable/disable the set-up process. .
Please refer to [SETUP]-bit description for details.
Automatic input signal detect registers are listed below:
*[Input Video Status Register]:
Sub Address 0x19
bit 7
bit 6
bit 5
bit 4
FIXED
UNDEF
ST_B/W
ST_VLF
bit 3
bit 2
bit 1
bit 0
ST_VCEN1 ST_VCEN0 ST_VSCF1 ST_VSCF0
*[ST-VSCF1:ST-VSCF0]-bit:
Input signal Sub-carrier verification result is indicated by [ST-VSCF1: ST-VSCF0]-bit.
[ST_VSCF1:ST_VSCF0]
Sub-Carrier Freq.[MHz]
[00]
3.57954545
[01]
3.57561188
[10]
3.582054
[11]
4.43361875
Note
*[ST-VCEN1:ST-VCEN0]-bit:
Color Encoding System Verification is indicated by [VCEN1:VCEN0]-bit.
[ST_VCEN1:ST_VCEN0]-bit
Type of Color Encode
00
NTSC
01
PAL
10
SECAM
11
Reserved
Note
*[ST-VLF]-bit:
Number of Lines per each Frame is indicated by [VLF]-bit.
[ST_VLF]-bit
Number of Lines
0
525lines
1
625lines
Note
MS0244-E-03
17
Confidential
2005 / 07