ID:15513 One or more extclk ports of enhanced PLL "<name>" must feed output pins when OPERATION_MODE parameter is set to EXTERNAL_FEEDBACK or ZERO_DELAY_BUFFER

CAUSE: You set the OPERATION_MODE parameter of the specified enhanced PLL to EXTERNAL_FEEDBACK or ZERO_DELAY_BUFFER, but the external clock ports of the specified enhanced PLL are feeding something other than an output pin. One of the external clock ports of the specified enhanced PLL must directly feed an output pin when the OPERATION_MODE parameter is set to EXTERNAL_FEEDBACK or ZERO_DELAY_BUFFER. This error usually occurs when you instantiate a megafunction directly in a text file rather than using the MegaWizard Plug-In Manager .

ACTION: Locate the source of the message to determine which megafunction parameter is causing the error. If you want to use the EXTERNAL_FEEDBACK or ZERO_DELAY_BUFFER parameter value, edit the design so one of the external clock ports of the specified enhanced PLL directly feeds an output pin. Otherwise, use the MegaWizard Plug-In Manager to specify the OPERATION_MODE parameter to NORMAL.