Omron CPM1A Capacity, Delay, Device, Interrupt, Point, Refreshing, Response time, Unit, Word

	Glossary
I/O capacity	The number of inputs and outputs that a PC is able to handle. This number
	ranges from around one hundred for smaller PCs to two thousand for the largest
	ones.
I/O delay	The delay in time from when a signal is sent to an output to when the status of the
	output is actually in effect or the delay in time from when the status of an input
	changes until the signal indicating the change in the status is received.
I/O device	A device connected to the I/O terminals on I/O Units. I/O devices may be either
	part of the Control System, if they function to help control other devices, or they
	may be part of the controlled system.
I/O interrupt	An interrupt generated by a signal from I/O.
I/O point	The place at which an input signal enters the PC System, or at which an output
	signal leaves the PC System. In physical terms, I/O points correspond to termi-
	nals or connector pins on a Unit; in terms of programming, an I/O points corre-
	spond to I/O bits in the IR area.
I/O refreshing	The process of updating output status sent to external devices so that it agrees
	with the status of output bits held in memory and of updating input bits in memory
	so that they agree with the status of inputs from external devices.
I/O response time	The time required for an output signal to be sent from the PC in response to an
	input signal received from an external device.
I/O Unit	The Units in a PC that are physically connected to I/O devices to input and output
	signals. I/O Units include Input Units and Output Units, each of which is available
	in a range of specifications.
I/O word	A word in the IR area that is allocated to a Unit in the PC System and is used to
	hold I/O status for that Unit.
IBM PC/AT or compatible	A computer that has similar architecture to, that is logically compatible with, and
	that can run software designed for an IBM PC/AT computer.
increment	Increasing a numeric value, usually by 1.
indirect address	An address whose contents indicates another address. The contents of the
	second address will be used as the actual operand.
initialization error	An error that occurs either in hardware or software during the PC System
	startup, i.e., during initialization.
initialize	Part of the startup process whereby some memory areas are cleared, system
	setup is checked, and default values are set.
input	The signal coming from an external device into the PC. The term input is often
	used abstractly or collectively to refer to incoming signals.
input bit	A bit in the IR area that is allocated to hold the status of an input.
input device	An external device that sends signals into the PC System.
input point	The point at which an input enters the PC System. Input points correspond
	physically to terminals or connector pins.
input signal	A change in the status of a connection entering the PC. Generally an input signal
	is said to exist when, for example, a connection point goes from low to high volt-
	age or from a nonconductive to a conductive state.
install	The preparation necessary to use a program or software package, such as the
	LSS or SSS, on a computer.

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