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Lilian_61's avatar
Lilian_61
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4 years ago

OCT usage in Cyclone V

Hi, I am using Cyclone V FPGA (5CGXFC5C7), and I want to use series 50ohm with calibration for signals. In the design, the signals that needs the OCT function are in Bank 3B & 4A. The PIN_AE11 is...
AqidAyman_Altera's avatar
AqidAyman_Altera
Icon for Regular Contributor rankRegular Contributor
4 years ago

Hi,


As per my understanding, to use the OCT function, the RZQ pins are connected to GND through an

external 100- or 240- reference resistor depending on the desired OCT impedance.


As for your question #2, you can just add the Weak Pull-Up Resistor column in the Editor table by customizing the table. And then you can just toggle the option to "On" for the pin that you desired to use the OCT function.


Regards,

Aqid Ayman


Lilian_61's avatar
Lilian_61
Icon for New Contributor rankNew Contributor
4 years ago

Hi，

The RZQ pin has connected to GND through an external 100ohm reference resistor on board.

From your reply, my understanding is the ALTOCT is not needed, and just do setting in Assignment Editor is ok.

And in Assignment Editor，I opened the OCT function for the pins like below.

But when I test on board, I found the signals gone on pins.

What I mean is, the pins work before I added the OCT function, but when I do the above setting, the pins doesn't work at all. Looks the setting disabled the pins function.

Could you help more on this? Not sure that my setting in Editor is correct.

Regards,

Lilian

  • Mklusal's avatar
    Mklusal
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    2 years ago

    Hi Lilian.

    Did you found a solution?

    I am facing the same issue.

    Milos