So has the time finally come? After eight years, will the faster, lower-pin count PCIe essentially win the day? Will PCI slots seemingly vanish from existence? Probably not. In fact, for some embedded applications, particularly in the military or industrial segments, it could be more than a decade before all peripheral manufacturers have adopted PCIe.
Since the official announcement of the Peripheral Component Interconnect Express (PCIe or PCI Express) standard in July 2002, marketers and engineers have been prognosticating about the demise of PCI Express' older parallel-bus cousin, PCI.
So has the time finally come? After eight years, will the faster, lower-pin count PCIe essentially win the day? Will PCI slots seemingly vanish from existence? Probably not. In fact, for some embedded applications, particularly in the military or industrial segments, it could be more than a decade before all peripheral manufacturers have adopted PCIe.
PCIe For Next Generation Designs
This does not however mean that designers will necessarily continue to support PCI in next generation components or chipsets. Consider the evolution of motherboard development as an example.
Not long ago, a motherboard would have included a CPU; a clock generator; a memory controller hub (Northbridge) with memory slots and, perhaps an AGP (accelerated graphics port) or PCIe bus for the graphics card; an I/O controller hub (Southbridge), and several PCI slots. 
Over time, the memory controller hub and I/O controller hub merged into a single platform controller hub (PCH) as memory control generally moved to the CPU. Representing the current state of motherboard solutions, the PCH still has several PCI slots attached. 
But if projections about next generation chipsets are correct the PCH will no longer have PCI slots in the near future-rather only PCIe will be supported. Essentially, chipset makers want to take full advantage of PCIe's high-speed, serial rate of 2.5Gbps for generation one PCIe products and 5Gbps for generation two products; isochronous data transfers, low-pin count, scalability, and, relative low power consumption.
Bridging to the Future
This means that if port 80 debuggers, card readers, or other PCI-based peripherals are going to work with newer computers and servers, something has to “bridge” the gap between new PCIe-only chipsets and PCI-only peripherals.
Fortunately, solutions abound, including the recently announced PED383 PCI Express bridge from IDT.
According to the IDT, “the PEB383 is a bridge that interfaces x1 PCI Express to 32b/66MHz PCI. …The PEB383 as a transparent bridge is plug and play that requires no special configuration and will initialize under standard BIOS enumeration.” 
To continue my motherboard example, the IDT PEB383 or a similar device would attached to the PCH, adding available PCI slots.
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