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Bus Bus # of
MBps Specification Name
Speed Width Devices
4 Asynchronous
5 MHz 8 bits 8 SCSI-1
MBps SCSI
5 Synchronous
5 MHz 8 bits 8 SCSI-1
MBps SCSI
10 16 Wide
5 MHz 16 SCSI-2
MBps bits SCSI
10 10 Fast
8 bits 8 SCSI-2
MBps MHz SCSI
20 10 16 Fast/Wide
16 SCSI-2
MBps MHz bits SCSI
20 20 SCSI-3 Ultra
8 bits 8
MBps MHz SPI SCSI
40 20 16 SCSI-3 Ultra/Wide
8
MBps MHz bits SPI SCSI
40 40 SCSI-3 Ultra2
8 bits 8
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80 40 16 SCSI-3 Ultra2/Wide
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160 40 16 SCSI-3 Ultra3
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50-pin internal ribbon (SCSI-1, SCSI-2, SCSI-3)
50-pin Alternative 2 Centronics (SCSI-1)
50-pin Alternative 1 high density (SCSI-2)
68-pin B-cable high density (SCSI-2)
68-pin Alternative 3 (SCSI-3)
80-pin Alternative 4 (SCSI-2, SCSI-3)
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