Article ID: 000079497 Content Type: Troubleshooting Last Reviewed: 11/21/2011

Clocked Video Output Incorrectly Aligns Start of Frame (vid_sof)

Environment

    Quartus® II Subscription Edition
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Critical Issue

Description

When you turn on frame locking in the Clocked Video Output it attempts to align its start of frame (output by the vid_sof signal) to the incoming start of frame signal (the sof signal). When it achieves this aligment, the IP core frame locks the output video (the start of frames are aligned) to the input video.

This issue affects systems enabling the frame locking functionality in the Clocked Video Output.

The output video frame lock is out by one cycle.

Resolution

To work around this issue, move the Clocked Video Output start of frame one cycle earlier. For example, if the start of frame required for Mode 1 is at sample 10, write 9 into bits 2 to 15 of the Mode1 SOF Sample register.

This issue will be fixed in a future version of the Video and Image Processing Suite.

Related Products

This article applies to 1 products

Intel® Programmable Devices

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