HP SCSI Host Bus Adapters bus, (OS), (PDC), (PIO), Memory, (MByte), devices, megabyte, (NVRAM ), component, Processor, peripheral, peripheral, programmed, queue tags, motherboard

megabyte	A measure of computer storage equal to 1024 kilobytes.
(MByte)
motherboard	See mainboard. In some countries, the term motherboard is not appropriate.
multi-tasking	The initiation and control of more than one sequence of operations. This allows programs to
	operate in parallel.
multi-threading	The simultaneous accessing of data by more than one SCSI device. This increases the aggregate
	data throughput.
N
Non-Volatile	An EEPROM used to store configuration information.
Random Access
Memory
(NVRAM )
O
operating system	A program that organizes the internal activities of the computer and its peripheral devices. An
(OS)	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 when CRC is not used. 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	A local bus specification that allows connection of integrated peripheral controller components,
component	peripheral add-in boards, and processor/memory systems.
interconnect (PCI)
peripheral	A hardware device (such as a video monitor, disk drive, printer, or CD-ROM) used with a
devices	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.
port address	Also port number. The address through which commands are sent to a host bus adapter. This
	address is assigned by the PCI bus.
port number	See port address.
Processor	The system firmware on HP PA-RISC systems. It provides basic read/write capability. Usually
Dependent Code	kept as firmware (ROM based). The system firmware on the main board of a computer is used
(PDC)	to boot and control the system.
programmed	A way the CPU can transfer data to and from memory via the computer’s I/O ports. PIO can
input/output	be faster than DMA, but requires CPU time.
(PIO)
Q
queue tags	A way to keep track of multiple commands while allowing increased throughput on the SCSI
	bus.
R
Random Access	In general, the computer’s primary working memory in which program instructions and data
Memory (RAM)	are stored and are accessible to the CPU. Information can be written to and read from RAM.
	The contents of RAM are lost when the computer is turned off.

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