The PCI bus is a high speed impedance controlled bus that operates at 3.3 volts. It cannot be simply connected to the pins of a typical microcontroller. It is possible to connect a microcontroller to PCI and this is typically done with a chip called a PCI bridge chip. However I have found, in the consideration of many designs in the past, that this is usually not cost effective. Usually a microcontroller such as 8052 is being used in a product becasue of its $2 to $10 cost figures. If you add a $15 to $25 bridge chip you can see that it defeats the while point of using an 8052 in the first place.

That said however there are still many market applications that need PCI interfacing. If you want to design to PCI you need to purchase the PCI specification from the PCI Special Interest group [you can do search on the web to find the site]. Distribution of the specification in a free way on the public forum is VERY tightly controlled. [I.E, if you find the spec on some web site someplace it is unlikely that the web site will exist for long!!].

I do not suggest trying to think that direct design to the PCI bus with discrete components is something you want to do. You could easly use well over your allotted project time just getting started.

For the reasons I have stated above you will find that the market place has addressed PCI interfacing in three ways.....

1) There are available PCI bridge chips that convert a local bus (like a microcontroller bus) to a PCI bus structure.

2) There are available embedded processors that have direct PCI interfacing built onto the part. You will find that these are high end parts in terms of bit width, clock frequency, and cost.

3) You can find that FPGA vendors are offering programmable logic solutions that can interface directly to PCI. Some have placed an direct piece of PCI hardware on the side of their chip whilest others have made their FPGA I/O cells PCI compliant and then offer (for a fee) some IP to program a PCI controller into a portion of the FPGA.

Of these three solutions the microcontroller with the onboard PCI interface is the best solution when you need to be a bus master. The FPGA solution is the best if you are trying to build something of the ilk of a peripheral function.

I hope all this info helps.
Mike