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REV. B
ADV7330
–53–
APPENDIX 1—COPY GENERATION
MANAGEMENT SYSTEM
HD CGMS Data Registers 2–0
[Subaddress 21h, 22h, 23h]
HD CGMS is available in 525p mode only, conforming to
‘CGMS-A EIA-J CPR1204-1, Transfer Method of Video ID
Information Using Vertical Blanking Interval (525p system),
March 1998’, and IEC61880, 1998, Video systems (525/60) —
video and accompanied data using the vertical blanking interval-
analog interface.
When HD CGMS is enabled [Subaddress 12h, Bit 6 = 1], CGMS
data is inserted on Line 41. The HD CGMS data registers are
to be found at address 21h, 22h, 23h.
SD CGMS Data Registers 2–0
[Subaddress 59h, 5Ah, 5Bh]
The ADV7330 supports copy generation management system
(CGMS) conforming to the standard. CGMS data is transmitted
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 output
on odd and even fields. CGMS data can be transmitted only
when the ADV7330 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 reference pulse of the
same amplitude and duration as a CGMS bit; see Figure 54.
HD CGMS Data Registers
[Subaddress 12h, Bit 6]
The ADV7330 supports copy generation management system
(CGMS) in HDTV mode (720p and 1080i) in accordance to
EIAJ CPR-1204-2. The HD CGMS data registers are to be found
at Addresses 21h, 22h, and 23h.
720p System
CGMS data is applied to Line 24 of the luminance vertical
blanking interval.
1080i System
CGMS data is applied to Line 19 and also on Line 582 of the
luminance vertical blanking interval.
CGMS CRC Functionality
If SD CGMS CRC [Address 59h, Bit 4] or PS/HD CGMS CRC
[Subaddress 12h, Bit 7] is set to Logic 1, the last six bits,
C19–C14, which comprise the 6-bit CRC check sequence, are
calculated automatically on the ADV7330 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 calculation of the CRC sequence is based on
the polynomial x
6
+ x + 1 with a preset value of 111111. If SD
CGMS CRC [Address 59h, Bit 4] or PS/HD CGMS CRC
[Subaddress 12h, Bit 7] is set to Logic 0, all 20 bits (C0–C19)
are output directly from the CGMS registers (no CRC calcu-
lated, 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 = x
6
+ x + 1 (preset to 111111).
Table XVII.
Bit
Function
WORD0
B1
B2
B3
WORD0
B4, B5, B6
1
16:9
Letterbox
0
4:3
Normal
Aspect ratio
Display format
Undefined
Identification information about video and
other signals (e.g., audio)
WORD1
B7, B8, B9, B10
WORD2
B11, B12, B13, B14 Identification signal and information
incidental to Word 0
Identification signal incidental to Word 0