Omron CPM1A operation manual Wdt

	Glossary
unmasked bit	A bit whose status is effective. See masked bit.
unsigned binary	A binary value that is stored in memory without any indication of whether it is
	positive or negative.
unsigned decimal	One-word hexadecimal values can be displayed at the Programming Console
	as decimal values from 0 to 65,535.
uploading	The process of transferring a program or data from a lower-level or slave com-
	puter to a higher-level or host computer. If a Programming Devices is involved,
	the Programming Device is considered the host computer.
watchdog timer	A timer within the system that ensures that the scan time stays within specified
	limits. When limits are reached, either warnings are given or PC operation is
	stopped depending on the particular limit that is reached.
WDT	See watchdog timer.
word	A unit of data storage in memory that consists of 16 bits. All data areas consists
	of words. Some data areas can be accessed only by words; others, by either
	words or bits.
word address	The location in memory where a word of data is stored. A word address must
	specify (sometimes by default) the data area and the number of the word that is
	being addressed.
work area	A part of memory containing work words/bits.
work bit	A bit in a work word.
work word	A word that can be used for data calculation or other manipulation in program-
	ming, i.e., a ‘work space’ in memory. A large portion of the IR area is always
	reserved for work words. Parts of other areas not required for special purposes
	may also be used as work words.
write protect switch	A switch used to write-protect the contents of a storage device, e.g., a floppy
	disk. If the hole on the upper left of a floppy disk is open, the information on this
	floppy disk cannot be altered.
write-protect	A state in which the contents of a storage device can be read but cannot be
	altered.

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