Omron SYSMAC C200HW-PCS01-EV1, Operation Manual

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Glossary
address A number used to identify the location of data or programming instructions in
memory or to identify the location of a network or a unit in a network.
advertisement The process of sending out information to make resources available to other
devices, e.g., sending information to other nodes in a network to make windows
available for communications.
allocation The process by which the PC assigns certain bits or words in memory for various
functions. This includes pairing I/O bits to I/O points on Units.
area See data area and memory area.
ARP Address Resolution Protocol: Determines the Ethernet address (i.e., physical
address) by broadcasting based on the target IP address.
ASCII Short for American Standard Code for Information Interchange. ASCII is used to
code characters for output to printers and other external devices.
asynchronous execution Execution of programs and servicing operations in which program execution
and servicing are not synchronized with each other.
Auxiliary Area A PC data area allocated to flags and control bits.
back-up A copy made of existing data to ensure that the data will not be lost even if the
original data is corrupted or erased.
baud rate The data transmission speed between two devices in a system measured in bits
per second.
BCD Short for binary-coded decimal.
binary A number system where all numbers are expressed in base 2, i.e., numbers are
written using only 0’s and 1’s. Each group of four binary bits is equivalent to one
hexadecimal digit. Binary data in memory is thus often expressed in hexadeci-
mal for convenience.
binary-coded decimal A system used to represent numbers so that every four binary bits is numerically
equivalent to one decimal digit.
bit The smallest piece of information that can be represented on a computer. A bit
has the value of either zero or one, corresponding to the electrical signals ON
and OFF. A bit represents one binary digit. Some bits at particular addresses are
allocated to special purposes, such as holding the status of input from external
devices, while other bits are available for general use in programming.
bit address The location in memory where a bit of data is stored. A bit address specifies the
data area and word that is being addressed as well as the number of the bit
within the word.
broadcast The process of sending data simultaneously to all nodes on a single network and
used to test network communications.
buffer A temporary storage space for data in a computerized device.