1 video display mode selection, 1 image timing – Texas Instruments TMS320C64x DSP User Manual
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Video Display Mode Selection
Video Display Port
4-2
SPRU629
4.1
Video Display Mode Selection
The video display module operates in one of three modes as listed in
Table 4–1. The DMODE bits are in the video display control register (VDCTL).
The Y/C and 16/20-bit raw display modes may only be selected if the DCDIS
bit in the video port control register (VPCTL) is cleared to 0.
Table 4–1. Video Display Mode Selection
DMODE Bits
Mode
Description
000
8-Bit ITU-R BT.656
Display
Digital video output is in YCbCr 4:2:2 with 8-bit resolution
multiplexed in ITU-R BT.656 format.
001
10-Bit ITU-R BT.656
Display
Digital video output is in YCbCr 4:2:2 with 10-bit resolution
multiplexed in ITU-R BT.656 format.
010
8-Bit Raw Display
8-bit data output
011
10-Bit Raw Display
10-bit data output
100
8-Bit Y/C Display
Digital video is output in YCbCr 4:2:2 with 8-bit resolution on
parallel Y and Cb/Cr multiplexed channels.
101
10-Bit Y/C Display
Digital video is output in YCbCr 4:2:2 with 10-bit resolution on
parallel Y and Cb/Cr multiplexed channels.
110
16-Bit Raw Display
16-bit data output.
111
20-Bit Raw Display
20-bit data output.
4.1.1
Image Timing
Display devices generate interlaced images by controlling the vertical retrace
timing. The video display module emits a data stream used to generate a
displayed image. An NTSC-compatible interlaced image with field and line
information is shown in Figure 4–1. A progressive-scan image (SMPTE 296M
compatible) is shown in Figure 4–2.
The active video area represents the pixels visible on the display. The active
video area begins after the horizontal and vertical blanking intervals. The
image area output by the video display module can be a subset of the active
area. The relationship between frame, active video area, and image area is
presented in Figure 4–3 for interlaced video and in Figure 4–4 for progressive
video. The video display module generates timing for frames, active video
areas within frames, and images within the active video area.