cx25840 Conexant Systems, Inc., cx25840 Datasheet - Page 227

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

CX25840/1/2/3 Data Sheet
5.6.3
102284B
8/3/05
Horizontal Blanking Delay Low
[7:0]
Horizontal Blanking Delay High
[7:4]
[3:2]
[1:0]
Horizontal Active High
[7:6]
[5:0]
Burst Gate Delay
[7:0]
Bits
Bits
Bits
Bits
RW
RW
RZ
RW
RZ
RW
RW
Type
Type
Type
Type
Autoconfiguration Parameters
0x7A
0000
00
00
00
0x00
0x5B
Default
Default
Default
Default
The user can write the following registers, or allow them to be set automatically based
on either the specified or detected video format. The user can also let the hardware
configure these registers based on the video format, and overwrite selected parameters
to customize the mode.
If the ACFG_DIS bit (MODE_CTRL) is left cleared, the hardware will set these
registers when either of the following happens:
When the ACFG_DIS bit is set, the hardware will never modify the values written by
the programmer to these registers.
The user specifies a specific mode by writing the VID_FMT_SEL
(MODE_CTRL) field.
The user specifies the autodetect mode in the VID_FMT_SEL (MOD_CTRL)
field, and the autodetect hardware detects a mode change.
BGDEL_CNT
HBLANK_CNT_LOW
HACTIVE_CNT_LOW
RESERVED
HBLANK_CNT_HIGH
RESERVED
HACTIVE_CNT_HIGH
Name
Name
Name
Name
Conexant
Lower 8 bits of horizontal blanking delay. It is number of
scaled pixels in the horizontal active and horizontal blanking
region of the line.
Lower nibble of horizontal active region duration. It is the
number of pixels in the active region of the line.
scaled pixels in the horizontal active and horizontal blanking
region of the line.
Burst gate delay. This value is used to generate the window
during which the color burst is sampled. It is the delay, in
pixel clocks, between the leading edge of hsync and the
center of the 4-pixel wide burst accumulate window.
Upper 2 bits of horizontal blanking delay. It is number of
Upper 6 bits of horizontal active region. It is number of
pixels in the active region of the line.
Description
Description
Description
Description
Address 0x473
Address 0x470
Address 0x471
Address 0x472
Register Map
5-85