I have been trying to forward 2 clocks, one of them is 12.5MHz, and the other one is 25MHz. when i used an oscilloscope to check the signal, it was not a square wave, and it was like a capacitence wave, as shown in figure 1. Figure 1l Notice that there are jumpers connected to the probes of the oscilloscope. Same applied when connecting the oscilloscope to the gnd of the board. Could you please help me to know how to generate the square wave of the clock ???

  • \$\begingroup\$ FYI, I used Arty A7 100T board. Vivado software, wondering if its a design thing? like the IP block i am using or the port type that i am using to forward the clock? Or the code? or the oscilloscop settings \$\endgroup\$ Mar 2 at 13:03
  • \$\begingroup\$ What is the bandwidth of your oscilloscope and scope probe? \$\endgroup\$ Mar 2 at 13:08
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    \$\begingroup\$ I have no idea what you mean by "forwarding" a clock! \$\endgroup\$
    – pipe
    Mar 2 at 14:42
  • \$\begingroup\$ As pictured, the oscilloscope is measuring the oscilloscope's own test pattern. You are supposed to adjust the oscilloscope (especially the probe compensation) to make this a square wave. \$\endgroup\$
    – user253751
    Mar 2 at 14:52
  • \$\begingroup\$ could you please explain how can I do that?. will be really appreciated. \$\endgroup\$ Mar 2 at 15:38

1 Answer 1


Set the probe on x10, make sure there is no BW (Bandwidth) limit set in the oscilloscope on the active channel and carefully adjust the probe compensation (an adjustment screw in the BNC end of the scope probe- use a screwdriver that fits properly) to get as perfect a square wave display as possible.

If the probe is not compatible with the oscilloscope you may not be able to adjust it properly.

  • \$\begingroup\$ appreciate your advice, will try that too \$\endgroup\$ Mar 2 at 15:39

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