Differences between the Clocking Wizard and the Legacy DCM and PLL Wizards - 1.0 English

There are several changes to the GUI and the wizard use model as described in the following subsections.

Primitive Selection

The old wizards required you to choose the correct GUI (DCM or PLL) before configuring the desired primitive.

The new Clocking Wizard automatically selects the appropriate primitive and configures it based on desired parameters. You can choose to override this choice in the event that multiple primitives are available, as is the case for the Spartan®-6 device family.

Symbol Pin Activation

The old wizards had a symbol with clickable pins to enable a port.

For the new Clocking Wizard, the symbol shows the ports that are currently active. To enable a port, enable the appropriate feature in the GUI. For example, enabling the secondary input clock enables the CLK_IN2 and CLK_IN_SEL ports and activates those ports in the symbol.

Parameter Override

The new Clocking Wizard allows you to override any calculated parameter within the wizard by switching to override mode.

Port Display Conventions

The new Clocking Wizard displays the superset of ports covering all device families. Ports that are not available for the selected target device are dimmed out. Information on the legal ports for a specific primitive can be found in the device family-specific FPGA or clocking resources on the Xilinx Support web page.

Visibility of Clock Ports

The new Clocking Wizard provides a clocking network that matches the your requirements rather than making clock ports visible. As a result, your clock names will not match the exact names for the primitive. For example, while the “first” clock available for the MMCM is CLKOUT0, the highest priority clock available to you is actually named CLK_OUT1.

GUI Information Gathering Order