ASAHI KASEI
[AK8817/18]
( a-3 ) HDI and VDI relation in each Frame
( a-3-1 ) NTSC ( Frame ) 525 Line 480 active lines
The First Field ( ODD )
263 lines
7
240 lines
23
525
1
2
3
4
5
6
22
261
262
263
264
HDI
VDI
* )VDI negative-going should be fed during the time from 3 clocks prior to negative-going of HDI at L4 till 3 clocks prior to positive-going of HDI.
VDI positive-going can occurs at arbitrary location, but keep VDI low for 3 line duration time as a rough idea.
The Second Field ( EVEN )
262 lines
240 lines
286
263
264
265
266
267
268
269
270
285
524
525
1
2
HDI
VDI
High
* ) VDI negative-going is not required for the Second Field. It is required for the First Field only ( VDI fed during the Second Field is ignored ).
Rev.001E
27
2009 / 12
AKM [ ASAHI KASEI MICROSYSTEMS ]
