How can I turn off PLL on opal kelly XEM 3010-1500p

Spartan-3 USB 2.0 Modules
1

I’m using the opal kelly to configure my circuits. After I finish configuring the circuits, I just need several opal kelly output pins to be at constant voltage (vdd or gnd), so I want to turn off PLL and any clock on the opal kelly board.

Is this possible? Can the voltages still hold after the clocks are off? Thanks.

2

I’m not exactly sure what you’re after, but you can refer to the Cypress CY22393 to see if this is possible. When you un-check “enable” through the FrontPanel Application, the corresponding output is disabled.

3

Thanks for the answer, do you know how to disable the PLL with C++ API? I’m not controlling with FrontPanel.

The reason I want to turn off the PLL is that right now the opal kelly board is injecting some noise to my circuit through the shared gnd. Therefore I want to turn off everything after I’m done configuring my circuit with OK borad.

Thanks again!

4

See the API documentation:

http://www.opalkelly.com/library/FrontPanel4API/index.html

The PLL settings are available through the PLL classes (okCPLL22393 in this case).

5

Thanks, I just tried to get PLL info, but I couldn’t get the code working, can you help me?

    //after xem=initXEM()
okCPLL22393 *pll = new okCPLL22393;
xem->GetPLL22393Configuration(*pll);

The program will return with exception at the function GetPLL22393Configuration;
with error code 0x10001a00, and the pll is void (0x0000). What should I do differently? Thanks.