bt865a Conexant Systems, Inc., bt865a Datasheet - Page 25

• Manufacturer Part Number: bt865a
• Description: Ycrcb To Ntsc/pal Digital Video Encoder
• Manufacturer: Conexant Systems, Inc.

Bt864A/Bt865A Data Sheet
1.5.1
1.5.2
Table 1-2.
100138C
02/17/03
NTSC/PAL–MCCIR601
PAL–B, D, G, H, I, N, Nc
CCIR601
NTSC/PAL–M Square Pixel
PAL–B, D, G, H, I, N, Nc
Square Pixel
GENERAL NOTE:
1. Tolerances apply to slave mode. Cumulative errors over color frame interval may result in subcarrier glitches.
2. Due to upsampling filter response, pixels near the boundary of the active definition will be reduced in amplitude due to
averaging with the blank level.
Operating Mode
Field Resolution and Clock Rates for Various Modes of Operation
Sync and Burst Timing
Reset
If the RESET* pin is held low during a single rising edge of CLK, the subcarrier
phase is set to zero, and the horizontal and vertical counters are held to the first pixel
and second line of FIELD1. Counting resumes on the first rising edge of CLK after
rising RESET*.
A software reset will occur immediately after writing a 1 to register SRESET. This
will reset all software-programmable register bits to zero.
On power-up, the Bt864A/Bt865A will automatically perform a timing and software
reset. The power-up state has the following configuration: interlaced, NTSC CCIR601
black burst (no active video), and zero chroma scaling. Setting register EACTIVE will
enable active video. On power-up, the DACs are disabled for 8 fields or until register
0x67 (0xCE as 8-bit address) is written.
Table 1-2
Horizontal
Porch = 0
711
702
647
767
Active Luminance Resolution
lists the resolutions and clock rates for the various modes of operation.
Interlaced
(pixels)
Field
Non
241
287
241
287
Vertical
Conexant
Interlaced
Frame
482
575
482
575
Horizontal
858 ± 1
864 ± 1
780 ± 1
944 ± 1
Total Resolution (pixels)
Interlaced
262 ± 1/4
312 ± 1/4
262 ± 1/4
312 ± 1/4
Non
Vertical
262.5 ± 1/4
312.5 ± 1/4
262.5 ± 1/4
312.5 ± 1/4
Interlaced
Circuit Description
Luminance
Frequency
13.5000
13.5000
12.2727
14.7500
(MHz)
Pixel
1-15