Occasional Contributorok,thanks for your answer，now,i have Redesigned circuit。
Frequent ContributorHi,
As per user guide 7.3.2. CLKUSR (intel.com) it seems you cannot use it. Because For transceiver calibration, CLKUSR must be a free-running clock running between 100 MHz to 125 MHz at power-up depending on the device’s configuration scheme as shown in the following table. Transceiver calibration starts utilizing the CLKUSR during device configuration and may continue to use it even when the device enters user mode.
Note: CLKUSR cannot be used as the reference clock for PLL.
Thank you
Kshitij Goel
Occasional Contributorthanks for your reply，if so,for transceiver calibration, it seems that must be provided a 100mhz clk on the clkusr pin？there are no other methods to solve this question,is this?
Can I use a clock not from clkusr pin for calibration while in user mode that program is running?（use other pin input clock）
