PCIA series of standards that govern hardware communicationTypically sets up devices and creates a Memory Map to allow device communicationResourcesAccessing PCI Express Configuration Registers: http://www.csit-sun.pub.ro/~cpop/Documentatie_SMP/Intel_Microprocessor_Systems/Intel_ProcessorNew/Intel%20White%20Paper/Accessing%20PCI%20Express%20Configuration%20Registers%20Using%20Intel%20Chipsets.pdf