PCI Configuration Space - A well known port address on x86 architecture where a PCI bus master can read/write registers in order to find other PCI devices and their functions and configure them as far as memory mapping and interrupts as a minimum.
PCI Interrupt Routing - PCI interrupts A-D can be routed onto x86 legacy interrupts IRQ0-15 in order to allow PCI devices to interrupt an x86 core.
PCI-Express - previously known as 3GIO, this standard is a scalable differential serial bus architecture for 2.5 Gbps mainboard interconnection and peripheral connection.
Peak-Up - a computer vision algorithm which finds a bright spot or the center of an object by segmenting an image and finding the centroid of a target within the image.
Pending Task - a VxWorks task state which indicates the task is blocking on a resource not presently available.
Period Jitter - when the period of a service request is not constant.
Period Transform - a real-time theory adjustment to a services characteristics to simplify analysis or to elevate importance of a service whereby the services period is assumed to be shorter than it really is.