Why are the number of lines per frame being incorrectly detected?
This happens in the following situations:
Typically, these changes should happen at the same cycle, but there could be cases where they are not aligned.
This is a known issue that is to be addressed in the next release of the Video Timing Controller IP.
This problem has been fixed in the Video Timing Controller 2.1 Rev2 patch.
To obtain the patch, see (Xilinx Answer 35096)
For a detailed list of LogiCORE IP Video Timing Controller Release Notes and Known Issues, see (Xilinx Answer 32754)