B&R Automation PC 620, Руководство пользователя

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Appendix A • Glossary
Automation PC 620 with 945GME N270 CPU board User's Manual V 1.10
MB
Megabyte (1 MB = 220 or 1,048,576 bytes).
Microprocessor
Highly integrated circuit with the functionality of a CPU, normally housed on a single chip. It
comprises a control unit, arithmetic and logic unit, several registers and a link system for
connecting memory and peripheral components. The main performance features are the internal
and external data bus and address bus widths, the command set and the clock frequency.
Additionally, a choice can be made between CISC and RISC processors. The first commercially
available worldwide microprocessor was the Intel 4004. It came on the market in 1971.
MIPS
Million instructions per second > Measurement for the computing speed of computers.
Motherboard
A circuit board that houses the main components of a computer such as the CPU switching
circuit, co-processors, RAM, ROM for firmware, interface circuits, and expansion slots for
hardware expansions.
MTBF
An abbreviation for " M ean t ime b etween f ailure". The average time which passes before a
hardware component fails and repair is needed. This time is usually expressed in thousands or
ten thousands of hours, sometimes known as power-on hours (POH).
MTCX
An abbreviation for » M ain t enance C ontroller E X tended«. The MTCX is an independent
processor system that provides additional functions for a B&R industrial PC that are not available
with a normal PC. The MTC communicates with the B&R industrial PC via the ISA bus (using a
couple register).
Multitasking
Multitasking is an operating mode in an operating system that allows several computer tasks to
be executed virtually simultaneously.
OEM
"O riginal E quipment M anufacturer"; A company that integrates third-party and in-house
manufactured components into their own product range and then distributes these products
under its own name.
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