SC2200 datasheet(344/433 Pages) NSC

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344

Revision 3.0

Video Processor Module (Continued)

14:8

m(Defines m PLL2 Value). Relevant when SEL_REG_CAL (bit 20) = 1. The following formula is used for calculating the

frequency using m and n values:

Fvco

= OSCCLK * Km/Kn

= m + 1

=n +1

OSCCLK = 27 MHz

7:4

Reserved

3:0

n (Defines n PLL2 Value). Relevant when SEL_REG_CAL (bit 20) = 1. The following formula is used for calculating the fre-

quency using m and n values:

Fvco

= OSCCLK * Km/Kn

= m + 1

=n +1

OSCCL

= 27 MHz

Offset 30h-33h

Reserved

Reset Value: 00000000h

Offset 34h-37h

Reserved

Reset Value: 00000000h

Offset 38h-3Bh

Reserved

Reset Value: 00000000h

Offset 3Ch-3Fh

Video Downscaler Control Register (R/W)

Reset Value: 00000000h

Controls the characteristics of the integrated video downscaler.

31:7

Reserved

DTS (Downscale Type Select).

0: Type A (Downscale formula is 1/m+1, m pixels are dropped, 1 pixel is kept).

1: Type B (Downscale formula is m/m+1, m pixels are kept, 1 pixel is dropped).

Reserved

4:1

DFS (Downscale Factor Select). Determines the downscale factor to be programmed into these bits, where m is used to

derive the desired downscale factor depending on bit 6 (DTS).

DCF (Downscaler and Filtering). Enables/disables downscaler and filtering logic.

0: Disable.

1: Enable.

Note:

No downscaling support for RGB 5:6:5 and YUV 4:2:0 video formats.

Offset 40h-43h

Video Downscaler Coefficient Register (R/W)

Reset Value: 00000000h

Indicates filter coefficients. The filters can be programmed independently to increase video quality when the downscaler is implemented.

Valid values for each filter coefficient are 0-15. The sum of coefficients must be 16. FLT_CO_4 is used with the earliest pixels and

FLT_CO_1 is used with the latest. Only luminance values of pixels are filtered.