The PCI-X LogiCORE contains numerous files designated with a particular suffix such as "n", "ne", "s", "x", "xe", and "xf." For example the Verilog wrapper files are named pcix_lc_64x.v, pcix_lc_64x, and so on. What do these suffixes mean?
The PCI-X LogiCORE operates in one of the following three modes; each one requires a single bitstream:
- PCI mode only at 33 MHz
- PCI-X mode only up to 133 MHz
- Dual Mode - PCI at 33 MHz and PCI-X at 66 MHz
The suffixes identify which files should be used with a particular mode of operation, as follows:
N - PCI Mode at 33 MHz in a Virtex-II, Virtex-II Pro, or Virtex-4 device
NE - PCI Mode at 33 MHz in a Virtex-E device
S - Dual Mode (PCI at 33 MHz and PCI-X at 66 MHz) in a Virtex-II or Virtex-II Pro device
X - PCI-X Mode at 66 MHz in a Virtex-II or Virtex-II Pro device or PCI-X Mode up to 133 MHz in Virtex-4
XE - PCI-X Mode at 66 MHz in a Virtex-E device
XF - PCI-X Mode up to 133 MHz in a Virtex-II or Virtex-II Pro device
It is important to use the correct file for the given design requirements. For more information on combining these files with the appropriate UCF files and devices, refer to Chapter 3 of the PCI-X Implementation Guide found in the "docs" directory included with the PCI-X LogiCORE zip file. You can also access this document online at:
For more information on the PCI-X core operation modes, see (Xilinx Answer 17809).