Omron CPM1A Data link area, Data movement instruction, Data sharing, Data trace, Debug, Digit

	Glossary
data link	An automatic data transmission operation that allows PCs or Units within PC to
	pass data back and forth via common data areas.
data link area	A common data area established through a data link.
data movement instruction	An instruction used to move data from one location in memory to another. The
	data in the original memory location is left unchanged.
data sharing	The process in which common data areas or common data words are created
	between two or more PCs.
data trace	A process in which changes in the contents of specific memory locations are
	recorded during program execution.
data transfer	Moving data from one memory location to another, either within the same device
	or between different devices connected via a communications line or network.
debug	A process by which a draft program is corrected until it operates as intended.
	Debugging includes both the removal of syntax errors, as well as the fine-tuning
	of timing and coordination of control operations.
decimal	A number system where numbers are expressed to the base 10. In a PC all data
	is ultimately stored in binary form, four binary bits are often used to represent
	one decimal digit, via a system called binary-coded decimal.
decrement	Decreasing a numeric value, usually by 1.
default	A value automatically set by the PC when the user does not specifically set
	another value. Many devices will assume such default conditions upon the
	application of power.
definer	A number used as an operand for an instruction but that serves to define the
	instruction itself, rather that the data on which the instruction is to operate. Defin-
	ers include jump numbers, subroutine numbers, etc.
destination	The location where an instruction places the data on which it is operating, as
	opposed to the location from which data is taken for use in the instruction. The
	location from which data is taken is called the source.
differentiated instruction	An instruction that is executed only once each time its execution condition goes
	from OFF to ON. Non-differentiated instructions are executed for each scan as
	long as the execution condition stays ON.
differentiation instruction	An instruction used to ensure that the operand bit is never turned ON for more
	than one scan after the execution condition goes either from OFF to ON for a
	Differentiate Up instruction or from ON to OFF for a Differentiate Down instruc-
	tion.
digit	A unit of storage in memory that consists of four bits.
digit designator	An operand that is used to designate the digit or digits of a word to be used by an
	instruction.
DIN track	A rail designed to fit into grooves on various devices to allow the devices to be
	quickly and easily mounted to it.
DIP switch	Dual in-line package switch, an array of pins in a signal package that is mounted
	to a circuit board and is used to set operating parameters.
direct output	A method in which program execution results are output immediately to elimi-
	nate the affects of the cycle time.
distributed control	A automation concept in which control of each portion of an automated system is
	located near the devices actually being controlled, i.e., control is decentralized

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