Omron SYSMAC C200HW-PCS01-EV1, Operation Manual

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Glossary
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overflow The state where the capacity of a data storage location has been exceeded.
overwrite Changing the content of a memory location so that the previous content is lost.
parity Adjustment of the number of ON bits in a word or other unit of data so that the
total is always an even number or always an odd number. Parity is generally
used to check the accuracy of data after being transmitted by confirming that the
number of ON bits is still even or still odd.
parity check Checking parity to ensure that transmitted data has not been corrupted.
PC An acronym for Programmable Controller.
PC card Memory card used with the PC Card Unit. PCMCIA 2.1-compliant PC cards
and/or memory cards on the market, such as SRAM, ATA, and FLASH memory
cards, can be used.
PC Card Unit This Unit provides various functions for using PC cards with SYSMAC C200HX/
HG/HE Programmable Controllers. CIO, DM, and EM data (but not the user pro-
gram) can be loaded and saved between C200HX/HG/HE Programmable Con-
trollers and Memory Cards inserted in the PC Card Unit.
PC Setup A group of operating parameters set in the PC from a Programming Device to
control PC operation.
Peripheral Device Devices connected to a PC System to aid in system operation. Peripheral
devices include printers, programming devices, external storage media, etc.
peripheral servicing Processing signals to and from peripheral devices, including refreshing, com-
munications processing, interrupts, etc.
present value The current value registered in a device at any instant during its operation. Pres-
ent value is abbreviated as PV. The use of this term is generally restricted to tim-
ers and counters.
Programmable Controller A computerized device that can accept inputs from external devices and gener-
ate outputs to external devices according to a program held in memory. Pro-
grammable Controllers are used to automate control of external devices.
Although single-unit Programmable Controllers are available, building-block
Programmable Controllers are constructed from separate components. Such
Programmable Controllers are formed only when enough of these separate
components are assembled to form a functional assembly, i.e., there is no one
individual Unit called a PC.
Programming Device A Peripheral Device used to input a program into a PC or to alter or monitor a
program already held in the PC. There are dedicated programming devices,
such as Programming Consoles, and there are non-dedicated devices, such as
a host computer.
PROM Programmable read-only memory; a type of ROM into which the program or
data may be written after manufacture, by a customer, but which is fixed from
that time on.
PROM Writer A peripheral device used to write programs and other data into a ROM for per-
manent storage and application.
prompt A message or symbol that appears on a display to request input from the opera-
tor.