The Cache Coherent Interconnect for Accelerators (CCIX) transaction layer requirements are implemented by the optional virtual channel 1 (VC1) in the design. Note that VC1 storage is in addition to the PCI Express-compliant virtual channel 0 (VC0) storage. The CCIX transaction layer interfaces with the CCIX protocol layer is implemented externally to the PCIe ports over the CCIX transaction layer (ARM CXS) hard interface. For more information, see the Versal Adaptive SoC CPM CCIX Architecture Manual (AM016).