Maxtor 10K III N egotiated R ate Information Page -F ield D escriptions

SCSI Description

5-32 Maxtor Atlas 10K III

N egotiated R ate Information Page -F ield D escriptions

Transfer Period Factor Applicable values of this field are provided in Appendix B.

REQ / ACK Offset

This is the negotiated value of Req / Ack offs et bet w een the initiator and

the t arget. For Si ngle Tr ansiti on (ST) da ta tran sfers, the REQ /ACK Offs et is

the maximum number of REQ assertions allowed to be outstandi ng before

a corresponding ACK assertion is received at the target : Data t ransfer size

may be 1 or 2 bytes. For Double Transition (DT) data tr ansfers, the REQ/

ACK Offset is the maximum number of REQ assert ions all owed to be out-

standing before a corresponding ACK assert ion is received at the target:

Dat a transfer size is 2 bytes.

AIP Asynchronous Informa ti on Protection. If = 1, dri ve supports AIP. If = 0,

device do es not support AIP.

AIPD Asy nchr onous Inf ormatio n Protec tion Gen eratio n Disabl ed. I f = 1, AI P gen-

eration is disabled. If = 0, AIP generation i s enabled.

AIPCE Asy nchronous Inf ormatio n Protec tion Ch ecking E nabl ed. If = 1, AIP pr otec -

tion is enabl ed. If = 0, AIP protection is disabled.

TWE Tr ansfer Width Exponent. The transfer width is 2n bytes. If set to 0, 1 byte

is selected; if set to 1, 2 bytes are selected.

PARL Parallel Protocol. When = 1 , this field indicates the negotiation occurr ed

with a Paral l el Protoco l message form at. When = 0, this fiel d indicat es the

negotiation occurred with a Synchronou s Data Request message format.

FAIR Fairness. When set = 1, the Fair ness algorit hm is enabled. When set = 0,

the algorithm is di sabled.

SYNC Synchronous Mode. When set = 1, the data transfer bus is operating in

synchronous mode. When set = 0, the data transfer bus is operating in

asynchronous mode.

QAS

(Note that the value of

this field must be 0 if the

value in PARL is 0)

Quick Ar britr ate Suppor t Enable. W hen = 0, in dicates tha t QAS is to be dis-

abled when received from initiator and that QAS is disabled when received

from target. When = 1, indicates that QAS is to be enabled when received

from initiator and that QAS is enabled when received from target. See

Appendix B.

(Note that the value of

this field must be 0 if the

value in PARL is 0)

Double Transition Enable. When = 0, indi cates that DT DATA is to be dis-

abled when re cei ved from init iator and that DT DATA phases are disabled

when r eceived from tar get. When = 1, indica tes that DT DATA phas es are

to be ena b le d w h en re c e iv e d fro m in itia to r and th a t D T D AT A ph a s es ar e

enabled when received from target. See Appendix B.

(Note that the value of

this field must be 0 if the

value in PARL is 0)

Information Units Enable. When = 0 , in dicates that information unit tr ans-

fers will not be us ed when rece ived fr om the in itiat or and t hat i nforma tion

unit transfers are di sabled when rec eived from the target. When = 1, indi-

cates that information unit transfers will be used when received from the

initiator and that information unit transfers are enabled when received from

the tar get. See Appendix B.