Cgms And Wss; Figure 110: Wss (625I) Waveform - Analog Devices Advantiv ADV7604 Hardware Manual

11.11.2 CGMS and WSS

The CGMS and WSS convey the same type of information for different video standards. WSS is a
625i standard while CGMS is a 525i, 525p, 625p, 720p, and 1080i standard. Hence, the CGMS and
WSS readback registers are shared. WSS is biphase coded and the VDP does a biphase decoding to
produce the 14 raw WSS bits to be available in the CGMS and WSS readback I
CGMS_WSS_AVL bit is set when this data is available.
STATUS_CLEAR_WSS_CGMS , VDP Map, Address 0x78, [2], Write only
Function
STATUS_CLEAR_WSS_
CGMS
0
1
STATUS_WSS_CGMS , VDP Map, Address 0x40, [2], Read only
Function
STATUS_WSS_CGMS
0
1
VDP_CGMS_WSS_DATA[23:0] , VDP Map, Address 0x43, [7:0], Address 0x44, [7:0], Address
0x45, [7:0], Read only
Function
VDP_CGMS_WSS_DATA
[23:0]
xxxx xxxx xxxx xxxx xxxx xxxx
0x43[7:0]
0x44[7:0]
0x45[7:0]
Refer to Figure 110 and
Rev. F August 2010
Description
Not necessary to write 0 since
STATUS_CLEAR_WSS_CGMS is a self clearing bit
Refreshes the CGMS and WSS readback registers
Description
CGMS/WSS not detected
CGMS/WSS detected
Description
Decoded CGMS[23:0] (525i)/WSS[13:0] (625i) data
VDP_CGMS_WSS_DATA[23:16]
VDP_CGMS_WSS_DATA[15:8]
VDP_CGMS_WSS_DATA[7:0]
2
Figure 111 for the I C bit to WSS/CGMS bit mapping.

Figure 110: WSS (625i) Waveform

344
ADV7604
2
C registers and the