Maxtor Atlas SCSI Drive 15K II, Руководство по эксплуатации продукта

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Appendix B
B-2 Maxtor Atlas 15K
Table B-2 Transfer Period Factor Field Values When PARL = 0
B.2 Settings for the QAS, DT, and IU fields
Table C-3 provides valid bit combinations for the QAS, DT, and IU fields of the
INQUIRY command’s Negotiated Rate Information Page (Section 5.11.2.7 of this
manual). Only the combinations shown in the table are valid; all other combinations
are reserved.
Table B-3 Settings for the QAS, DT, and IU Fields of the Negotiated Rate Information Page
(INQUIRY Command)
Code Description
00h – 09h Reserved.
0Ah Transfer period = 25 ns (Fast-40 data is latched every 25 ns).
0Bh Transfer period = 30 ns (Fast-40 data is latched every 30 ns).
OCh Transfer period = 50 ns (Fast-20 data is latched using a transfer period of less than
or equal to 96 ns and greater than or equal to 50 ns).
0Dh – 18h Transfer period = the period factor x 4 (Fast-20 data is latched using a transfer
period of less than or equal to 96 ns and greater than or equal to 50 ns).
19h – 31h Transfer period = the period factor x 4 (Fast-10 data is latched using a transfer
period of less than or equal to 196 ns and greater than or equal to 100 ns).
32h - FFh Transfer period = the period factor x 4 (Fast-5 data is latched using a transfer period
of less than or equal to 1020 ns and greater than or equal to 200 ns).
QAS DT IU Description
0 0 0 Selects Single Transition phases. Use ST DATA IN and ST DATA OUT
phases to transfer data
0 1 0 Use DT DATA IN and DT DATA OUT phases with data group transfers.
0 1 1 Use DT DATA IN and DT DATA OUT phases with information unit trans-
fers.
1 1 1 Use DT DATA IN and DT DATA OUT phases with information unit transfers
and use QAS for arbitration.