IBM PCI Dual Channel Ultra3 SCSI Adapter, Installation And Using Manual

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Run Ultra3 Devices at Ultra2 Data Transfer Rates
To run at Ultra3 data rates (160 MB/s on a 16-bit bus), parallel protocol request (PPR)
must be enabled. If PPR is not enabled, then the maximum data transfer rates available
will be Ultra2 (80 MB/s on a 16-bit bus).
Attention: Use this procedure when connecting either a 2104 Model DL1 or a 2104
Model TL1 Expandable Storage Plus system.
Notes:
1. To enable PPR, the wide attribute must be set.
2. Both the PPR and wide attributes are enabled by default.
To run Ultra3 devices at Ultra2 data transfer rates by disabling PPR, do the following:
1. At the command prompt, type
smitty scsia
, and press Enter.
2. Select Change / Show Characteristics of a SCSI Adapter.
3. Select your adapter from the list, and press Enter.
Example: (This screen varies based on the adapter you select.)
Change / Show Characteristics of a SCSI Adapter
Type or select values in entry fields.
Enter AFTER making all desired changes.
[Entry Fields]
SCSI Adapter scsi4
Description Wide/Ultra-3 SCSI I/O
Status Available
Location 20-58
PCI-SCSI I/O Processor type 53C1010
Adapter card SCSI ID [7]
BATTERY backed adapter no
Negotiate after SCSI check condition yes
Maximum synchronous data transfer rate (mHz) 40
Wide bus enabled yes
SCSI bus transceiver alternative LVD/SE
Number of DMA bursts per PCI bus ownership 64
DMA bus memory LENGTH (0x200000)
Target mode bus memory length (0x40000)
Ultra speed on SE bus with external cable disable
Bus mode limiting wide transfer with 2 cables SE
Parallel protocol request enabled..............yes
Domain validation enabled......................yes
Apply change to DATABASE only no
4. Select Parallel protocol request enabled.
5. Press F4.
6. Select no, and press Enter.
7. Press Enter again.
8. If the change was successful, press F10 to exit SMIT.
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Installation and Using Guide