CVO frequency

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there doesn't seem to be a rule on when you need .sdc files. some get generated in the project directory, some are in the IP install directory, and some are embedded in the core

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I didn't know there were SDC files to add for the CVI and CVO. I have never had timing problems with them, but I suppose I should be using the SDC files just to be sure.

I find it really annoying that the SDC files for generated IP do not automatically get included in all cases. Just yesterday I wasted several hours trying to get a DDR SDRAM controller working until I realized I forgot to include the SDC file. Of course, the solder ball between two of the data pins didn't help either...

Kind of like rock-paper-scissors except solder balls always win.

Today I switched over to using the 10.0 tools on another PC. I noticed that the CVO and CVI .sdc files were automatically added to the project - whereas they weren't in 9.0.

Another note. I was using the Timing Advisor to increase my FMax. As I added in the recommended options my FMax dropped. I'm sure it all depends on the design but something to keep in mind and not just blindly go with their recommendations.

I also noticed today that the .sdc file for the CVI is added automatically in Quartus II 10.0. I also checked the VIP user guide, and it still indicates you need to add them manually. It only mentions adding SDC files for CVI and CVO, however I searched my install folder and found all of the following:

C:\altera\10.0\ip\altera\clocked_video_input\alt_vipcti100_cvi.sdc

C:\altera\10.0\ip\altera\clocked_video_output\alt_vipitc100_cvo.sdc

C:\altera\10.0\ip\altera\deinterlacer\alt_vip_dil.sdc

C:\altera\10.0\ip\altera\frame_buffer\alt_vip_vfb.sdc

C:\altera\10.0\ip\altera\frame_reader\alt_vipvfr100_vfr.sdc

I didn't try all of the cases, but at least for the frame buffer (VFB), the sdc file is not added automatically.

interesting, so just take the time to check the cores that interface to the outside world

rogerleo: the method used in larger than 1080p video streams was actually multiple 1080p streams stitched together. either way looks like you'll have to write some logic