flow of data to and from system memory by blocks, as opposed to PIO (Programmed I/O) where the flow is byte by byte.

device driver A program that allows a microprocessor (through the operating system) to direct the operation of a peripheral device.

differential A hardware configuration for connecting SCSI devices. It uses a pair of lines for each signal transfer (as opposed to single-ended SCSI which references each SCSI signal to a common ground).

EEPROM (electronically erasable programmable read-only memory) A memory chip typically used to store configuration information. See

NVRAM.

EISA (Extended Industry Standard Architecture) An extension of the 16-bit ISA bus standard. It allows devices to perform 32-bit data transfers.

external SCSI device A SCSI device installed outside the computer cabinet. External SCSI devices are connected in a chain using shielded cables.

Fast SCSI A standard for SCSI data transfers. It allows a transfer rate of up to 10 MBytes/sec over an 8-bit SCSI bus, and up to 20 MBytes/sec over a 16-bit SCSI bus.

FCC Federal Communications Commission.

file A named collection of information, usually stored on a disk.

firmware Software that is permanently stored in ROM. In the case of BIOS, it can be accessed during boot time without the aid of an operating or file system.

hard disk A rigid disk permanently sealed into a drive cartridge. A hard disk can store very large amounts of information.

host The computer system in which a SCSI host adapter is installed. It uses the SCSI host adapter to transfer information to and from devices attached to the SCSI bus.

host bus adapter (HBA) A circuit board and/or integrated circuit device that provides a SCSI bus connection to the computer system.

internal SCSI device A SCSI device installed inside the computer cabinet. These devices are connected in a chain using an unshielded ribbon cable.

IRQ (interrupt request channel) A path through which a device can get the immediate attention of the computer’s CPU. The PCI bus assigns an IRQ path

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