EVAL-ADV7180LFEBZ Analog Devices Inc, EVAL-ADV7180LFEBZ Datasheet - Page 61

• Manufacturer Part Number: EVAL-ADV7180LFEBZ
• Description: BOARD EVAL FOR ADV7180 LFCSP
• Manufacturer: Analog Devices Inc

Specifications of EVAL-ADV7180LFEBZ

• Main Purpose: Video, SDTV Video Decoder - NTSC, PAL, SECAM
• Embedded: No
• Utilized Ic / Part: ADV7180
• Primary Attributes: CVBS (Composite), Y/C (S-video), and YPrPb (Component) Inputs
• Secondary Attributes: 8-bit ITU-R BT.656 YCrCb 4:2:2 Output
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

I
Teletext
Because teletext is a high data rate standard, the decoded bytes
are available only as ancillary data. However, a TTXT_AVL bit
has been provided in I
VDP has detected teletext. Note that the TTXT_AVL bit is a
plain status bit and does not use the protocol identified in the
I
TTXT_AVL, Teletext Detected Status, Address 0x78[7],
User Sub Map, Read Only
When TTXT_AVL is 0, teletext was not detected.
When TTXT_AVL is 1, teletext was detected.
WST Packet Decoding
For WST only, the VDP decodes the magazine and row address
of teletext packets and further decodes the packet’s 8 × 4
hamming coded words. This feature can be disabled using the
WST_PKT_DECODE_DISABLE bit (Bit 3, Register 0x60, user
sub map). This feature is valid for WST only.
Table 80. WST Packet Description
Packet
Header Packet (X/00)
Text Packets (X/01 to X/25)
8/30 (Format 1) Packet
Design Code = 0000 or 0001
UTC
8/30 (Format 2) Packet
Design Code = 0010 or 0011
PDC
X/26, X/27, X/28, X/29, X/30, X/31
1
2
2
For X/26, X/28, and X/29, further decoding needs 24 × 18 hamming decoding. Not supported at present.
C Interface section.
C READBACK REGISTERS
2
C so that the user can check whether the
1
Byte
1
2
3
4
5
11
1
2
3
1
2
3
4
11
24
1
2
3
4
11
24
1
2
3
4
st
nd
rd
th
th
st
nd
rd
st
nd
rd
th
st
nd
rd
th
st
nd
rd
th
th
th
th
th
th
to 10
to 42
to 10
to 10
to 42
to 42
to 23
to 42
to 23
to 42
th
nd
th
th
nd
nd
rd
nd
rd
nd
Rev. F | Page 61 of 116
WST_PKT_DECODE_DISABLE, Disable Hamming
Decoding of Bytes in WST, Address 0x60[3], User Sub Map
Setting WST_PKT_DECODE_DISABLE to 0 enables hamming
decoding of WST packets.
Setting WST_PKT_DECODE_DISABLE to 1 (default) disables
hamming decoding of WST packets.
For hamming-coded bytes, the dehammed nibbles are output
along with some error information from the hamming decoder
as follows:
•
•
Table 79. Error Bits in the Dehammed Output Byte
E[1:0]
00
01
10
11
Table 80 describes the WST packets that are decoded.
Description
Magazine number—Dehammed Byte 4
Row number—Dehammed Byte 5
Page number—Dehammed Byte 6
Page number—Dehammed Byte 7
Control bytes—Dehammed Byte 8 to Byte 13
Raw data bytes
Magazine number—Dehammed Byte 4
Row number—Dehammed Byte 5
Raw data bytes
Magazine number—Dehammed Byte 4
Row number—Dehammed Byte 5
Design code—Dehammed Byte 6
Dehammed initial teletext page, Byte 7 to Byte 12
UTC bytes—Dehammed Byte 13 to Byte 25
Raw status bytes
Magazine number—Dehammed Byte 4
Row number—Dehammed Byte 5
Design code—Dehammed Byte 6
Dehammed initial teletext page, Byte 7 to Byte 12
PDC bytes—Dehammed Byte 13 to Byte 25
Raw status bytes
Magazine number—Dehammed Byte 4
Row number—Dehammed Byte 5
Design code—Dehammed Byte 6
Raw data bytes
Input hamming coded byte: {D3, P3, D2, P2, D1, P1, D0, P0}
(bits in decoded order)
Output dehammed byte: {E1, E0, 0, 0, D3', D2', D1', D0'}
(Di' – corrected bits, Ei error information).
Error Information
No errors detected
Error in P4
Double error
Single error found and corrected
Output Data Bits
in Nibble
Okay
Okay
Bad
Okay
ADV7180