ADV7194KST(Rev0) View Datasheet(PDF) - Analog Devices

Part Name

Description

Manufacturer

ADV7194KST
(Rev.:Rev0)

Professional Extended-10 Video Encoder with 54 MHz Oversampling

Analog Devices 

ADV7194

APPENDIX 3

COPY GENERATION MANAGEMENT SYSTEM (CGMS)

The ADV7194 supports Copy Generation Management System

(CGMS) conforming to the standard. CGMS data is transmit-

ted on Line 20 of the odd fields and Line 283 of even fields.

Bits C/W05 and C/W06 control whether or not CGMS data is

put out on ODD and EVEN fields. CGMS data can only be

transmitted when the ADV7194 is configured in NTSC mode.

The CGMS data is 20 bits long, the function of each of these

bits is as shown below. The CGMS data is preceded by a refer-

ence pulse of the same amplitude and duration as a CGMS bit, see

Figure 96. These bits are put out from the configuration registers in

the following order: C/W00 = C16, C/W01 = C17, C/W02 =

C18, C/W03 = C19, C/W10 = C8, C/W11 = C9, C/W12 =

C10, C/W13 = C11, C/W14 = C12, C/W15 = C13, C/W16 =

C14, C/W17 = C15, C/W20 = C0, C/W21 = C1, C/W22 = C2,

C/W23 = C3, C/W24 = C4, C/W25 = C5, C/W26 = C6, C/W27

= C7. If the bit C/W04 is set to a Logic 1, the last six bits C19–C14

which comprise the 6-bit CRC check sequence are calculated auto-

matically on the ADV7194 based on the lower 14 bits (C0–C13)

of the data in the data registers and output with the remaining

14 bits to form the complete 20 bits of the CGMS data. The calcu-

lation of the CRC sequence is based on the polynomial X6 + X + 1

with a preset value of 111111. If C/W04 is set to a Logic 0 then

all 20 bits (C0–C19) are output directly from the CGMS regis-

ters (no CRC calculated, must be calculated by the user).

Function of CGMS Bits

Word 0 – 6 Bits

Word 1 – 4 Bits

Word 2 – 6 Bits

CRC – 6 Bits CRC Polynomial = X6 + X + 1 (Preset to

111111)

WORD 0

B1

B2

B3

Aspect Ratio

Display Format

Undefined

1

16:9

Letterbox

0

4:3

Normal

WORD 0

B4, B5, B6

WORD 1

B7, B8, B9,

B10

Identification Information About Video and

Other Signals (e.g., Audio)

Identification Signal Incidental to Word 0

WORD 2

B11, B12,

B13, B14

Identification Signal and Information

Incidental to Word 0

100 IRE

70 IRE

REF

CRC SEQUENCE

C0 C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 C14 C15 C16 C17 C18 C19

0 IRE

–40 IRE

11.2␮s

49.1␮s ؎ 0.5␮s

2.235␮s ؎ 20ns

Figure 96. CGMS Waveform Diagram

–48–

REV. 0

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