Description
This may occur for one of the following reasons:
- The EPC1 device is loaded with a design called demo_board.gdf, which is a
pci_a
function with a memory unit as its local side. This file is also included in thepci_a
build. The PCI board walkthrough uses pci_top.gdf to configure the prototype board. This file only instantiates thepci_a
function and does not contain the local-side signals that are in demo_board.gdf. - The
pci_a
function does not support theLOCKn
signal. Make sure you tri-stateLOCKn
. Otherwise, it will drive out and contend with the PCI bus. - The local clock signal
l_clock
supplies the clock to the local side. It is an logic-cell-driven signal, and should not be used for the PCI clock signal because it has a larger skew. Use the provided PCI clock signal assigned to one of the global clock inputs.