Closed Captioning Readback Registers; Figure 107: Wss (625I) Waveform; Figure 108: Cgms (525I) Waveform - Analog Devices ADV7850 Hardware Manual

Function
vdp_status_wss_cgms
0 
1
vdp_cgms_wss_data[23:0], Addr 48 (VDP), Address 0x43[7:0]; Address 0x44[7:0]; Address 0x45[7:0] (Read Only)
This readback displays decoded data for CGMS type A and WSS.
Function
vdp_cgms_wss_data[23
:0]
vdp_cgms_wss_data[23:0
]
vdp_cgms_wss_data[13:0
]

Closed Captioning Readback Registers

10.3.3
Two bytes of decoded closed caption (CCAP) data are made available in the VDP readback registers. The
identifies the field from which the CCAP data was decoded.
status_clear_ccap, Addr 48 (VDP), Address 0x78[0] (Self-Clearing)
This control is used to refresh the CCAP status registers. This is a self-clearing bit.
Function
status_clear_ccap
0 
1
Rev. A May 2012
Description
WSS or CGMS type A data not detected
WSS or CGMS type A data detected
Description
decoded CGMS[23:0] data
decoded WSS[13:0] data

Figure 107: WSS (625i) Waveform

Figure 108: CGMS (525i) Waveform

Description
Do not refresh CCAP status registers
Refresh CCAP status registers
315
ADV7850
vdp_status_ccap_even_field