SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
Figure 11-63 shows VSYNC from Group 1 and HBLINK from Group 2 being used. Set USE_ACTVID_HSYNC_N=’0’ and DISCRETE_BASIC_MODE=’1’.
Also, no automatic parsing of vertical ancillary data will be performed so the Ancillary VPI port to the VPDMA should be disabled. All lines, including both vertical ancillary and active video, will appear in the Video DRAM buffer. Lines starting after an inactive to active transition on VSYNC will delineate a start of frame. Every data element strobed on the Pixel clock’s active edge will be stored in the Active Video Buffer.
In Figure 11-63, it is likely the HBLINK will toggle when VSYNC is active. In this case, setting USE_ACTVID_HSYNC_N=’0’ and DISCRETE_BASIC_MODE=’0’ mean that those lines appearing under the active VSYNC will be sent to the Ancillary Data Buffer. All other captured lines will be sent to the Active Video Buffer.
Figure 11-63 VSYNC and HBLNK