Low Voltage Differential (LVD) A robust design methodology that improves power consumption, data integrity, cable lengths, and support for multiple devices while providing a migration path for increased I/O performance.

M

main memory The part of a computer’s memory that is directly accessible by the CPU (usually synonymous with RAM).

mainboard A large circuit board that holds RAM, ROM, the microprocessor, custom integrated circuits, and other components that make a computer work. It also has expansion slots for host bus adapters and other plug-in boards.

megabyte (MByte) A measure of computer storage equal to 1024 kilobytes.

motherboard See mainboard. In some countries, the term motherboard is not appropriate.

multi-taskingThe initiation and control of more than one sequence of operations. This allows programs to operate in parallel.

multi-threadingThe simultaneous accessing of data by more than one SCSI device. This increases the aggregate data throughput.

N

Non-Volatile Random Access Memory (NVRAM ) An EEPROM used to store configuration information.

Glossary

pin-1 orientation

O

operating system (OS) A program that organizes the internal activities of the computer and its peripheral devices. An operating system performs basic tasks such as moving data to and from devices and managing information in memory. It also provides the user interface.

P

parity checking A way to verify the accuracy of data transmitted over the SCSI bus. One bit in the transfer is used to make the sum of all the 1 bits either odd or even (for odd or even parity). If the sum is not correct, an error message appears. SCSI uses odd parity for data transfer rates less than 160 MB/s.

peripheral component interconnect (PCI) A local bus specification that allows connection of integrated peripheral controller components, peripheral add-in boards, and processor/memory systems.

peripheral devices A hardware device (such as a video monitor, disk drive, printer, or CD-ROM) used with a computer and under the computer’s control. SCSI peripherals are controlled through a SCSI host bus adapter.

pin-1 orientation The alignment of pin 1 on a SCSI cable connector and the pin 1 position on the SCSI connector into which it is inserted. External SCSI cables are keyed to ensure proper alignment, but internal SCSI ribbon cables might not be.

Glossary

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