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Altera_Forum's avatar
Altera_Forum
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16 years ago

overflow and underflow of CVI&CVO

hi, I am dealing with ip core clocked video(CVI) in and clocked video out(CVO). And there is a pin named overflow on CVI, and a pin named underflow on CVO, my question is when an overflow or under...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Did you probe the underflow overflow pins on the Cyclone III board? If I remember this correctly, the output leds on the Cyclone III board are active low, so they should go OFF when they receive a HIGH signal. The leds light up when they receive a LOW signal creating the voltage difference needed between the anode cathode so that the current can flow.

I'm also experiencing CVO underflow in a design, just recently I posted a new thread, probable it's related to timing or bandwidth issues..not quite sure yet