56
http://www.TYAN.com
IDE (Integrated Device/Drive Electronics):
a simple, self-contained HDD interface. It can handle
drives up to 8.4 GB in size. Almost all IDEs sold now are in fact Enhanced IDEs (EIDEs), with
maximum capacity determined by the hardware controller.
IDE INT (IDE Interrupt):
a hardware interrupt signal that goes to the IDE.
I/O (Input/Output):
the connection between your computer and another piece of hardware (mouse,
keyboard, etc.)
IRQ (Interrupt Request):
an electronic request that runs from a hardware device to the CPU. The
interrupt controller assigns priorities to incoming requests and delivers them to the CPU. It is
important that there is only one device hooked up to each IRQ line; doubling up devices on IRQ
lines can lock up your system. Plug-n-Play operating systems can take care of these details for you.
Latency:
the amount of time that one part of a system spends waiting for another part to catch up.
This occurs most commonly when the system sends data out to a peripheral device and has to wait
for the peripheral to spread (peripherals tend to be slower than onboard system components).
NVRAM:
ROM and EEPROM are both examples of Non-Volatile RAM, memory that holds its data
without power. DRAM, in contrast, is volatile.
Parallel port:
transmits the bits of a byte on eight different wires at the same time.
PCI (Peripheral Component Interconnect):
a 32 or 64-bit local bus (data pathway) which is faster
than the ISA bus. Local buses are those which operate within a single system (as opposed to a
network bus, which connects multiple systems).
PCI PIO (PCI Programmable Input/Output) modes:
the data transfer modes used by IDE drives.
These modes use the CPU for data transfer (in contrast, DMA channels do not). PCI refers to the
type of bus used by these modes to communicate with the CPU.
PCI-to-PCI bridge:
allows you to connect multiple PCI devices onto one PCI slot.
Pipeline burst SRAM:
a fast secondary cache. It is used as a secondary cache because SRAM is
slower than SDRAM, but usually larger. Data is cached first to the faster primary cache, and then,
when the primary cache is full, to the slower secondary cache.
PnP (Plug-n-Play):
a design standard that has become ascendant in the industry. Plug-n-Play
devices require little set-up to use. Devices and operating systems that are not Plug-n-Play require
you to reconfigure your system each time you add or change any part of your hardware.
PXE (Preboot Execution Environment):
one of four components that together make up the Wired
for Management 2.0 baseline specification. PXE was designed to define a standard set of preboot
protocol services within a client with the goal of allowing networked-based booting to boot using
industry standard protocols.
RAID (Redundant Array of Independent Disks):
a way for the same data to be stored in different
places on many hard drives. By using this method, the data is stored redundantly and multiple hard
drives will appear as a single drive to the operating system. RAID level 0 is known as striping,
where data is striped (or overlapped) across multiple hard drives, but offers no fault-tolerance.
RAID level 1 is known as mirroring, which stores the data within at least two hard drives, but does
not stripe. RAID level 1 also allows for faster access time and fault-tolerance, since either hard
drive can be read at the same time. RAID level 0+1 is both striping and mirroring, providing fault-
tolerance, striping, and faster access all at the same time.
RAIDIOS:
RAID I/O Steering (Intel)
