Even if the TCK frequency setting of the USB-Blaster II download cable is changed using the jtagconfig command, as described in the related solution, the frequency setting may revert to the default value of 24MHz in the following cases:
- A jtagconfig command is executed when the USB-Blaster II download cable is removed from your PC.
- A jtagconfig command fails to recognize the USB-Blaster II download cable and shows an error.
- A JTAG operation like Hardware Setup is executed from the Quartus® II software when the USB-Blaster II download cable is removed from your PC.