Philips Semiconductors
Video Out
File: evo.fm5, modified 7/24/99
PRELIMINARY INFORMATION
7-15
7.13.3
Video Out Registers
The remaining VO registers and their fields are shown in
Table 7-8.Table 7-8. Video Out Register FIelds
Register
Field
Description
VO_CLOCK
FREQUENCY
VO_CLK frequency. See the DDS equation in
Figure 7-6, and PLL description in
VO_FRAME
FRAME LENGTH
Total number of lines per frame, the ending value of Frame Line Counter. Typically set to
525 or 625. Note frame counter counts from 1 to 525 or 625, consistent with CCIR 656 line
numbering.
FIELD 2 START
Start line number in Frame Line Counter where second eld of frame begins. If non inter-
laced pictures are desired, then the same value is programmed for eld 1 and eld 2.
eld 1 becomes frame 1 and eld 2 becomes frame 2.
FRAME PRESET
Value loaded into Frame Line Counter when frame timing edge is received on VO_IO2.
Note: currently this must be set to 1.
VO_FIELD
F1 VIDEO LINE
Line number in the Frame Line Counter of rst active video line of eld 1 of the frame.
F2 VIDEO LINE
Line number in the Frame Line Counter of rst active video line of eld 2 of the frame.
If non interlaced pictures are desired this is programmed to the same value as F1 VIDEO
LINE
F1 OLAP
Overlap of the SAV and EAV codes from eld 1 to eld 2. Overlap is dened as the delay in
lines from start of blanking for eld 2 until SAV and EAV codes for eld 2 are emitted. Typ-
ical values are +2 for 525/60 and +2 for 625/50.
F2 OLAP
Overlap in lines of the SAV and EAV code from eld 2 to eld 1. Overlap is dened as the
delay in lines from start of blanking for eld 1 until the SAV and EAV codes for eld 1 are
emitted. Typical values are +3 for 525/60 and –2 for 625/50. The negative value means
eld 1 blanking actually starts two lines before end of eld 2 of previous frame. This over-
VO_LINE
FRAME WIDTH
Total line length in pixels including blanking. This is also the ending value for the Frame
Pixel Counter. Lines always begin with horizontal blanking interval, and image starts after
blanking interval and runs to end of the line.
VIDEO PIXEL START
Pixel number in Frame Pixel Counter of starting pixel of active video area within the line.
Note: This must be even.
VO_IMAGE
IMAGE HEIGHT
Video Image line height in lines.
IMAGE WIDTH
Video Image line (scaled) output width in pixels. Must be even for upscaling by 2x.
VO_YTHR
Y THRESHOLD
Threshold image line number in the Image Line Counter for the YTR interrupt.
Can be reprogrammed on a frame by frame basis.
IMAGE VOFF
Image vertical offset in lines from the top of active video window.
IMAGE HOFF
Image horizontal offset in pixels from the start of active video window.
VO_OLSTART
OL START LINE
Starting image line of YUV overlay within the image. Zero indicates overlay starts at same
line as the image.
OL START PIXEL
Starting image pixel of the YUV overlay within the image. Zero indicates overlay starts at
same pixel as the image. Note: Must be even.
ALPHA ONE
Alpha blend value used for YUV 4:2:2+alpha format overlays when alpha bit = 1.
VO_OLHW
OVERLAY HEIGHT
Height of YUV overlay image in lines. The height of the overlay should be chosen such
that it does not extend beyond the image area.
OVERLAY WIDTH
Width of YUV overlay image in pixels. Note: must be even.
ALPHA ZERO
Alpha blend value used for YUV 4:2:2+alpha format overlays when alpha bit = 0.
VO_YADD
Y_BASE_ADR
BFR1BASE_ADR
In video refresh modes, Y-component starting byte address.
In data-streaming and message-passing mode, buffer 1 starting byte address. Note:
Must be 64-byte aligned in data-streaming mode. Note: Must be 4-byte aligned in mes-
sage passing mode.
VO_UADD
U_BASE_ADR
BFR2BASE_ADR
In video refresh modes, U-component starting byte address.
In data-streaming mode, buffer 2 starting byte address. Note: Must be 64-byte aligned
in data-streaming mode
Not used in message-passing mode.