Honored Contributor
Honored ContributorHi Guys,
I think that the CVI is confused, but I don't think that this is causing the image distortion. The main reason why is that without the control of the scaler, the system works. Unfortunately, I do need control of the scaler for our applicaiton; it's the main reason why we are not using off the shelf equipment for our application. Jake, the screen is upside down; the picture shows the top left of the screen, but the back of it. So there are extra pixels, pushing it to the right of the screen (from the front viewpoint). I should have put this note on the images, or flipped them for logical purposes. I am getting both overflow on cvi and underflow on my video out, but it is inconsistent, here is the outputs from my cvi and cvo registers as they are most recently reported by nios2 code (some are derived): Vid In Registers: Running Stable OVERFLOW Invalid Resolution Used Words: 0 A. Sample Cnt: 400 A. Line Count: 2f7 T. Sample Cnt: 540 T. Line Count: 324 Vid Out Registers: Control: 1 Status: 5 Interrupt: 0 Used Words: 4af Video Mode M: 0 Mode 1 Control: 1 Running UNDERFLOW NOT Locked Something strange is going on here. I have just upped the frequency of the vip path clock to 120MHz. The video coming in is at 110MHz pixel clock. This did not change the symptoms. I've tested with SVGA and XGA video at 50MHZ and 65MHz respectively and the problem is consistent. Next actions: 1) I'm considering moving to embedded syncs to see if that improves the performance of the CVI. 2) I'm also considering moving my frame buffer: CVI-> FB -> Scaler ->CVO. This has memory bandwidth disadvantages for our application but will be useful diagnostically.
