Compatibility Guide

194 Glossary
TSOP
Abbreviation for thin small outline package. A very thin, plastic, rectangular
surface mount chip package with gull-wing pins on its two short sides.
UART
Acronym for universal asynchronous receiver transmitter, the electronic circuit
that makes up the serial port.
UDP
Abbreviation for user datagram protocol.
UL
Abbreviation for Underwriters Laboratories.
UMB
Abbreviation for upper memory blocks.
unicode
A fixed width, 16-bit world wide character encoding, developed and maintained
by the Unicode Consortium.
upper memory area
The 384 KB of RAM located between 640 KB and 1 MB. If the system has an x86
or higher microprocessor, a utility called a memory manager can create UMBs
in the upper memory area, in which you can load device drivers and
memory-resident programs.
UPS
Abbreviation for uninterruptible power supply. A battery-powered unit that
automatically supplies power to your system in the event of an electrical failure.
URL
Abbreviation for Uniform Resource Locator (formerly Universal Resource
Locator).
USB
Abbreviation for Universal Serial Bus. A USB connector provides a single
connection point for multiple USB-compliant devices, such as mice, keyboards,
printers, and computer speakers. USB devices can also be connected and
disconnected while the system is running.