GS1503 Gennum Corporation, GS1503 Datasheet - Page 45

• Manufacturer Part Number: GS1503
• Description: HD Embedded Audio Codec
• Manufacturer: Gennum Corporation

2.5 VIDEO DATA PROCESSING
2.5.1 Video Signal Input Detection
The GS1503 will set the VIDEO_DET external pin HIGH
when three consecutive TRS are detected in the input video
signal. Also, the VIDEO_DET bit of Host Interface register
000h is set HIGH.
Register Settings
2.5.2 Video Input CRC Error Detection
The GS1503 will set the CRC_ERR external pin HIGH when
a CRC error is detected in the input video signal. Also, the
CRC_ERR bit 5 of Host Interface register 000h is set HIGH.
The number of CRC errors accumulated in one video frame
can be read form CRC_CNT[11:0] in Host Interface
registers 006h and 007h.
Register Settings
2.5.3 Video Output CRC Insertion
When the CRC_INS bit 4 of Host Interface register 000h is
set HIGH, the GS1503 will re-calculate the video line CRC
words. The re-calculated CRC words are inserted in the
video output signal. When CRC_INS is set LOW, the line
CRC words are not updated and existing CRC words at the
input of the device will be output unchanged.
Register Settings
2.5.4 Input Blanking
When VBLK_INS bit 3 of Host Interface register 008h is set
HIGH, the input video vertical blanking will be set to 040h
for the Luma channel and 200h for the Chroma channel.
When HBLK_INS bit 2 of Host Interface register 008h is set
HIGH, the input video horizontal blanking will be set to 040h
for the Luma channel and 200h for the Chroma channel.
The TRS, line number and CRC words will also be set to
blanking values.
CRC_CNT[11:0]
VIDEO_DET
CRC_ERR
CRC_INS
NAME
NAME
NAME
Video input signal detection (1: Detection)
Video input signal CRC error detection (1: Detection)
Video input signal CRC error accumulation in 1 video
frame
Video line CRC insertion (1: Insertion)
DESCRIPTION
DESCRIPTION
DESCRIPTION
45
The blanking function is performed at the output of the
GS1503 video data stream. If the HBLK_INS bit is set HIGH,
any embedded audio or control packets will be replaced
with blanking codes. The GS1503 will demultiplex data
contained in the packets, prior to the blanking function, and
output at the corresponding pins.
ADDRESS
ADDRESS
ADDRESS
000
000
006
007
000
BIT
BIT
3-0
7-0
BIT
6
5
4
SETTING
SETTING
SETTING
1
-
-
-
DEFAULT
DEFAULT
DEFAULT
15879 - 1
0
0
0
1