| Parity Checking | A way to verify the accuracy of data transmitted over the SCSI bus. The |
| parity 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, the |
| information may be retransmitted or an error message may appear. |
| Passive | The electrical connection required at each end of the SCSI bus, |
Termination | composed of a set of resistors. It improves the integrity of bus signals. |
| PCI | Peripheral Component Interconnect. A local bus specification that allows |
| connection of peripherals directly to computer memory. It bypasses the |
| slower ISA and EISA buses. |
A piece of hardware (such as a video monitor, disk drive, printer, or
The alignment of pin 1 on a SCSI cable connector and the
| PIO | Programmed Input/Output. A way the CPU can transfer data to and from |
| memory using the computer’s I/O ports. PIO is usually faster than DMA, |
| but requires CPU time. |
| Port Address | Also Port Number. The address through which commands are sent to a |
| host adapter board. This address is assigned by the PCI bus. |
| Port Number | See Port Address. |
| Queue Tags | A way to keep track of multiple commands that allow for increased |
| throughput on the SCSI bus. |
| RAM | Random Access Memory. The computer’s primary working memory in |
| which program instructions and data 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. |
| RISC Core | LSI Logic SCSI chips contain a RISC (Reduced Instruction Set |
| Computer) processor, programmed through microcode SCRIPTS. |
| ROM | Read Only Memory. Memory from which information can be read but not |
| changed. The contents of ROM are not erased when the computer is |
| turned off. |
Glossary of Terms and Abbreviations |