Specifications

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Glossary
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function together to capture and lock onto an input frequency. When locked onto the
input frequency, the PLL can maintain a stable, regulated output frequency (within
bounds) despite frequency variance at the input.
Physical Address: The address or location in memory where data is stored before it is
moved as memory remapping occurs. The physical address is that which appears on
the computer’s address bus when the CPU requests data from a memory address.
When remapping occurs, the data can be moved to a different memory location or
logical address.
Pinout: A diagram or table describing the location and function of pins on an
electrical connector.
Plastic Quad Flat Pack (PQFP): A popular package design for integrated circuits of
high complexity.
Power On Self Test (POST): A diagnostic routine which a computer runs at power
up. Along with other testing functions, this comprehensive test initializes the system
chipset and hardware, resets registers and flags, performs ROM checksums, and
checks disk drive devices and the keyboard interface.
Program: A set of instructions a computer follows to perform specific functions
relative to user need or system requirements. In a broad sense, a program is also
referred to as a software application, which can actually contain many related,
individual programs.
Programmable Array Logic (PAL): A semiconductor programmable ROM which
accepts customized logic gate programming to produce a desired sum-of-products
output function.
 R 
Random Access Memory (RAM): Memory in which the actual physical location of
a memory word has no effect on how long it takes to read from or write to that
location. In other words, the access time is the same for any address in memory. Most
semiconductor memories are RAM.
Read Only Memory (ROM): A broad class on semiconductor memories designed
for applications where the ratio of read operations to write operations is very high.
Technically, a ROM can be written to (programmed) only once, and this operation is
normally performed at the factory. Thereafter, information can be read from the
memory indefinitely.
Real Mode: The operational mode of Intelx86 CPUs that uses a segmented, offset
memory addressing method. These CPUs can address 1 MB of memory using real
mode.
Real Mode Address: A memory address composed of two 16-bit values: a segment
address and an offset quantity. A real mode address is constructed by shifting a