Quantum 10K II - Manual (Page 364)

Quantum Atlas 10K II Ultra 160/m SCSI Hard Disk Drives C–1
Appendix C
NEGOTIATED RATE INFORMATION PAGE REFERENCE
This appendix provides information about the INQUIRY command’s Negotiated Rate
Information Page that is not provided in Section 5.11.2.7. Specifically, it provides the codes and
meanings for the Transfer Period Factor field (byte 4) and a table that explains the allowable
settings for the QAS, DT, and IU fields (bits 2, 1, and 0, respectively, of byte 7).
C.1 TRANSFER PERIOD FACTOR FIELD
Table C-1 provides the codes and meanings allowed for the Transfer Period Factor field if the
value of PARL (Parallel Protocol, bit 2 of byte 6 of the Negotiated Rate Information Page) is 1.
Table C-2 provides the allowable codes when the value of PARL = 0.
Table C–1 Transfer Period Factor Field Values When PARL = 1
Code Description
00h – 08h Reserved.
09h Transfer period = 12.5 ns (Fast-80 is latched every 12.5 ns). This code is valid only if
the protocol options bits (QAS, DT, and IU) of the page have values selected that
support double transition (DT) data transfers.
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).