cx25840 Conexant Systems, Inc., cx25840 Datasheet - Page 225

• Manufacturer Part Number: cx25840
• Description: Video Decoder And Broadcast Audio
• Manufacturer: Conexant Systems, Inc.

CX25840/1/2/3 Data Sheet
102284B
8/3/05
VBI Custom 3 Frame Code Length
[7:5]
[4:0]
VBI Custom 3 Clock Run-in Period
[7:0]
VBI Custom 3 Clock Run-in Margin and Length
[7:4]
[3:0]
VBI Custom 3 Payload Length
[7:0]
Bits
Bits
Bits
Bits
RZ
RW
RW
RW
RW
RW
Type
Type
Type
Type
000
0x08
0x20
0xF
0x6
0x84
Default
Default
Default
Default
VBI3_CRI_TIME
RESERVED
VBI3_FC_LENGTH
VBI3_CRI_LENGTH
VBI3_CRI_MARGIN
VBI3_PAYLD_LENGTH
Name
Name
Name
Name
Conexant
Expected time period of clock run-in period in terms of halves
of the bit period specified in VBI3_BITINC. The algorithm
detects the number of edges specified in VBI3_CRI_LENGTH
and compares the elapsed time with this parameter. If the result
is within VBI3_CRI_MARGIN of this parameter, then the
waveform is decoded.
Number of clock run-in edges expected in the CRI period. This
does not include the edge that transitions into the frame start
code, and this is an N-1 parameter. For example, in a Teletext
waveform with 16 bit periods and 16 edges, program 0xF in
this register. For closed caption with 6.5 bit periods, but 13
edges, program 0xC
This field specifies the margin around VBI3_CRI_TIME in
which the measured time of the clock run-in period can fall.
See VBI3_CRI_TIME. This is in units of eights of the bit period
defined by VBI1_BITINC.
Number of start bits (or frame code bits)
Number of data bits to be captured, divided by two. If N is the
number of bits in the payload, program this register with N/2.
Description
Description
Description
Description
Address 0x46D
Address 0x46B
Address 0x46E
Address 0x46C
Register Map
5-83