TMS320AV7110 datasheet(51/131 Pages) TI

51 / 131 page

DSP

TMS320AV7110

Revision 3.1

10/08/99 22:18

Page 51

Table 24. Digital Output Control

SIGNALS

YCCTRL[1]

YCCTRL[0]

Component Y

Component Cb

Component Cr

VARIS code

The aspect ratio VARIS code includes 14 bits of data plus a 6-bit CRC, to make a total of 20 bits. In

NTSC the 14-bit data is specified as shown in Table 25.

Table 25. VARIS Code Specification

Bit Number

Contents

Communication aspect ratio: 1 = full mode (16:9), 0 = 4:3

Word0 A

Picture display system: 1 = letter box, 0 = normal

3Not used

Word0 B

Identifying information for the picture and other signals (sound signals)

that are related to the picture transmitted simultaneously

Word1

4-bit range

Identification code associated to Word0

Word2

4-bit range

Identification code associated to Word0 and other information

The 6-bit CRC is calculated, with the preset value to be 63, based on the equation

G(X) = X

+ X + 1

The 20-bit code is further packaged into 3 bytes according to the following format.

Table 26. Three Byte VARIS Code

1st Byte

---

Word0 B

Word0 A

2nd Byte

Word2

Word1

3rd Byte

VID_

---

CRC

The three byte VARIS code is constructed by the ARM as part of the initialization process. The code is

transmitted during the non-active video line starting from the 1st byte. The application can set the

VID_EN bit that signals the NTSC/PAL encoder to enable (1) or disable (0) the VARIS code. The

value of the Aspect Ratio bit depends on the setup of ‘AV7110 video output and the source bit stream

as shown in the Table 27. The application can change the video output format using an software API

call.

Table 27. Coding of Aspect Ratio in the VARIS Code

Source 4:3

Source 16:9

Video Out 4:3

4:3

Video Out 16:9

4:3

16:9

The timing of the VARIS output based on a 27 MHz clock is shown in the timing diagrams in Section

17.1. The timing of both 4:4:4 and 4:2:2 digital video output formats is also described there.

TMS320AV7110 датащи(PDF) 51 Page - Texas Instruments

TMS320AV7110 датащи(HTML) 51 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL