Adaptec PC/104, PCM-3420 manual Scsi Device

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SCSI (Small Computer Systems Interface)

A PC bus interface standard that defines standard physical and electrical connections for devices. SCSI provides a standard interface that enables many different kinds of devices, such as disk drives, magneto optical disks, CD-ROM drives, and tape drives to interface with the host computer.

SCSI DEVICE

A device such as a host adapter board, fixed disk drive or CD- ROM drive that conforms to the SCSI interface standard and is attached to a SCSI bus cable. The device may be an initiator, a target, or capable of both types of operation.

Single-ended SCSI (normal SCSI)

For each signal that needs to be sent across the bus, there exists a wire to carry it.

SYNCHRONOUSTRANSFER

A method of SCSI data transfer. With this type of data transfer, the SCSI host adapter and the SCSI device agree to a transfer rate that both support (this is known as synchronous negotiation). With this type of data transfer method, transfer rates of 5 MBytes/sec or 10 MBytes/sec (for FAST SCSI) are common.

Is SYNCHRONOUS faster than ASYNCHRONOUS?

Asynchronous is faster on short cables, while synchronous is faster on long cables. The reason has to do with the propagation delay of the cable; the turn around time of the silicon; and the interlocked nature of the asynchronous handshake.

Appendix C Glossary of Terms 51

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Contents PCM-3420 PC/104 Fast SCSI-2 Module Page Acknowledgements Copyright NoticePacking Set Contents Appendix a Installing PC/104 Modules Appendix B Pin AssignmentsAppendix C Glossary of Technical Terms39 General Information Introduction Product HighlightsPeripheral Device Support FeaturesSpecifications Technical SpecificationsPhysical and Environmental Specifications Board layout Page Hardware Installation Jumpers Label Function Jumpers and ConnectorsJP6 JP7 JP2 Locating Jumpers & Connectors Setting Jumpers Precautions Installing PCM-3420 ModuleFactory Default Settings JP2 Jumper Configuration ReferenceSD0 SD1 SD2 DMA DC1 DC2 This jumper block provides six major PCM-3420 operation mode CC000h CFFFFh Scsi Hard Disk Drive Connector CN1 Page EZ-SCSI Quick Reference System Requirements for Full Installa- tion Quick Start InstructionsWindows 95 or Windows NT DOS Windows/Windows for WorkgroupsTroubleshooting Tips Scsi Device TroubleshootingWindows 95/Windows NT Troubleshooting General Information Page General Information DOS and Windows 3.1x Device Driver Information for DOS/Windows 3.1x UsersDOS and Windows 3.1x Aspi Managers DOS Formatting UtilitiesLow-level Formatter scsifmt Formatter and Partitioner afdisk Removable Media Manager rmvtool Page Installing PC/104 Modules Installing PC/104 modules PC/104 Module Mounting Diagram Page Pin Assignments Pin Signal PC/104 Connectors J1 , J2Internal SCSI-2 Connector CN Page Glossary of Technical Terms Adaptec EZ-SCSI Termpwr GND Synchronous Transfer Bios Devicedriver DOS Partition Chronous Full Scsi IRQ Narrow Scsi device as opposed to Wide Scsi device Port I/O Address Scsi Device Taggedqueuing Termination Page Appendix C Glossary of Terms