beautypg.com

Scsi drives, Disconnect-reconnect page, Disconnect-reconnect page fields – HP Q153090901 User Manual

Page 78

background image

Commands

78

Disconnect-Reconnect page

SCSI drives

The Disconnect-Reconnect page has the following format for SCSI drives:

Disconnect-Reconnect page fields:

NOTE:

If the host does not grant disconnect privilege in its

IDENTIFY

message these

parameters become meaningless. The drive will stay connected on the bus for the duration of

an operation or until the host sends a mid-operation

IDENTIFY

granting disconnect privilege.

7

6

5

4

3

2

1

0

0

PS (0)

Rsvd (0)

Page Code {02h}

1

Additional Page Length {0Eh}

2

Buffer Full Ratio (0)

3

Buffer Empty Ratio (0)

4

(MSB)

Bus Inactivity Limit (0)

5

(LSB)

6

(MSB)

Disconnect Time Limit [0]

7

(LSB)

8

(MSB)

Connect Time Limit (0)

9

(LSB)

10

(MSB)

Maximum Burst Size [0]

11

(LSB)

12

Reserved (0)

DTDC (0)

13–15

Reserved (0)

Buffer Full Ratio

0 Buffer management is controlled by the drive, so this should always be zero.

Connect Time Limit

0 Buffer management is controlled by the drive, so this should always be zero.

Bus Inactivity Limit

0 This parameter is not supported and should be zero.

Disconnect Time Limit

0 This parameter is not supported and should be zero.

Connect Time Limit

0 This parameter is not supported and should be zero.

Maximum Burst Size

>0 The maximum amount of data that will be transferred during a data-in or

data-out phase before disconnecting. This field is in units of 512 bytes. The

maximum burst size that the drive supports is 127 (7Fh) blocks of 512 bytes,

that is, 64 KB less 512 bytes.

0 The drive may send bursts of any size. This is the default value.

DTDC

0 The Data Transfer Disconnect Control field is not supported and should be

zero.