Adaptec 29320LPE User Guide - Page 37

Sync Transfer Rate, Packetized, Initiate Wide Negotiation, Enable Disconnection - problems with

Get Adaptec 29320LPE - SCSI Card Storage Controller U320 320 MBps PDF manuals and user guides
UPC - 760884154762
View all Adaptec 29320LPE manuals
Add to My Manuals
Save this manual to your list of manuals

Page 37 highlights

Chapter 8: Configuring the Adaptec SCSI Card with SCSISelect ● 37 SCSI Device Configuration Options SCSI Device Configuration options can be set individually for each connected SCSI device. Note: To configure settings for a SCSI device, you must know its SCSI ID (see Using SCSI Disk Utilities on page 43). ● Sync Transfer Rate-(Default: 320) Determines the maximum synchronous data transfer rate that the SCSI card supports. We recommend that you leave the maximum (default) value of 320 MB/sec. ● Packetized-(Default: Yes) Packetized protocol is required to operate at 320 MB/sec. When enabled, this option is available if it is implemented in the device drivers. However, this option is not supported by the BIOS. ● QAS-(Default: Yes) Quick Arbitration and Selection reduces the overhead of control release on the SCSI bus from one device to another. This improvement reduces command overhead and maximizes bus utilization. When enabled, this option is available if it is implemented in the device drivers. However, this option is not supported by the BIOS. ● Initiate Wide Negotiation-(Default: Yes) Enables the SCSI card to initiate Wide Negotiation with the SCSI target. When set to Yes, the SCSI card attempts 16-bit data transfer (wide negotiation). When set to No, the SCSI card uses 8-bit data transfer unless the SCSI device requests wide negotiation. Note: Set Initiate Wide Negotiation to No if you are using an 8-bit SCSI device that hangs or exhibits other performance problems with 16-bit data transfer rate enabled. ● Enable Disconnection-(Default: Yes) When set to Yes, Enable Disconnection allows the SCSI device to disconnect from the SCSI bus. When set to No, the SCSI device cannot disconnect from the SCSI bus. Leave the setting at Yes if two or more SCSI devices are connected to the SCSI card. When Enable Disconnection is set to No, the SCSI device cannot disconnect from the SCSI bus, packetized transfers cannot occur, and transfer rates are set at Ultra 160 levels. ● Send Start Unit Command-(Default: Yes) When set to Yes, sends the Start Unit Command to the SCSI device at bootup. This reduces the load on a system's power supply by allowing the SCSI card to turn on SCSI devices one-by-one when the system boots; otherwise, all SCSI devices turn on at the same time. Note: Check the device documentation to make sure the device supports the command. On most devices, you must also change a switch or jumper setting on the device to enable the device to respond to the command. The following options have no effect if the SCSI card BIOS is disabled. (The SCSI card BIOS is normally enabled by default.) ● BIOS Multiple LUN Support-(Default: No) Leave this setting at No if the device does not have multiple LUNs. When set to Yes, the SCSI card BIOS provides boot support for a SCSI device with multiple LUNs (for example, a CD juke box device in which multiple CDs can be accessed simultaneously). ● Include in BIOS Scan-(Default: Yes) When set to Yes, the SCSI card BIOS controls the SCSI device if it is an INT 13 device (such as a SCSI disk drive) without device driver software. When set to No, the SCSI card BIOS does not control the SCSI device and device driver software is required. The BIOS can support up to eight INT 13 devices without an additional device driver.

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
Chapter 8: Configuring the Adaptec SCSI Card with SCSISelect
●
37
SCSI Device Configuration Options
SCSI Device Configuration options can be set individually for each connected SCSI device.
Note:
To configure settings for a SCSI device, you must know its SCSI ID (see
Using SCSI Disk
Utilities
on page 43
).
●
Sync Transfer Rate
—(Default: 320) Determines the maximum synchronous data transfer
rate that the SCSI card supports. We recommend that you leave the maximum (default)
value of 320 MB/sec.
●
Packetized
—(Default: Yes) Packetized protocol is required to operate at 320 MB/sec.
When enabled, this option is available if it is implemented in the device drivers. However,
this option is not supported by the BIOS.
●
QAS
—(Default: Yes) Quick Arbitration and Selection reduces the overhead of control
release on the SCSI bus from one device to another. This improvement reduces command
overhead and maximizes bus utilization. When enabled, this option is available if it is
implemented in the device drivers. However, this option is not supported by the BIOS.
●
Initiate Wide Negotiation
—(Default: Yes) Enables the SCSI card to initiate Wide
Negotiation with the SCSI target. When set to Yes, the SCSI card attempts 16-bit data
transfer (wide negotiation). When set to No, the SCSI card uses 8-bit data transfer unless
the SCSI device requests wide negotiation.
Note:
Set Initiate Wide Negotiation to No if you are using an 8-bit SCSI device that hangs or
exhibits other performance problems with 16-bit data transfer rate enabled.
●
Enable Disconnection
—(Default: Yes) When set to Yes, Enable Disconnection allows the
SCSI device to disconnect from the SCSI bus. When set to No, the SCSI device cannot
disconnect from the SCSI bus. Leave the setting at Yes if two or more SCSI devices are
connected to the SCSI card. When Enable Disconnection is set to No, the SCSI device
cannot disconnect from the SCSI bus, packetized transfers cannot occur, and transfer rates
are set at Ultra 160 levels.
●
Send Start Unit Command
—(Default: Yes) When set to Yes, sends the Start Unit
Command to the SCSI device at bootup. This reduces the load on a system’s power supply
by allowing the SCSI card to turn on SCSI devices one-by-one when the system boots;
otherwise, all SCSI devices turn on at the same time.
Note:
Check the device documentation to make sure the device supports the command. On
most devices, you must also change a switch or jumper setting on the device to enable the
device to respond to the command.
The following options have no effect if the SCSI card BIOS is disabled. (The SCSI card BIOS is
normally enabled by default.)
●
BIOS Multiple LUN Support
—(Default: No) Leave this setting at No if the device does not
have multiple LUNs. When set to Yes, the SCSI card BIOS provides boot support for a SCSI
device with multiple LUNs (for example, a CD juke box device in which multiple CDs can
be accessed simultaneously).
●
Include in BIOS Scan
—(Default: Yes) When set to Yes, the SCSI card BIOS controls the
SCSI device if it is an INT 13 device (such as a SCSI disk drive) without device driver
software. When set to No, the SCSI card BIOS does not control the SCSI device and device
driver software is required. The BIOS can support up to eight INT 13 devices without an
additional device driver.