1358_DPT_2012_EISA_SCSI

NEXTSTEP for Intel Processors

Title: DPT 2012/90 and DPT 2012/95 EISA SCSI Controllers
Entry Number: 1358
Last Updated: <<Date June 17, 1997>>

Product Vendor:
Distributed Processing Technology
140 Candace Drive
Maitland, FL 32751
USA

+1 (407) 830 5522 phone
+1 (407) 831 6432 bulletin board system
+1 (407) 260 5366 fax

Keywords: DPT, 2012, SCSI, EISA

Description:
The DPT 2012 SCSI Controller provides NEXTSTEP users with a high performance EISA bus to SCSI interface. Some of the notable features of this card are:

Up to 16MB of RAM cache

33MB/sec EISA transfer

EISA bus mastering

SCSI-2 and CCS compliant

10MB/sec SCSI sync transfer

CAM-compliant EATA interface

Overlapped commands

Scatter/gather

Automatic request sense

RAID support in hardware

Setup and Installation:
It is not necessary to change any jumpers on the DPT 2012/90 from the factory defaults. If you have a DPT 2012/95 with an integrated floppy controller be aware that the floppy is officially unsupported under NEXTSTEP Release 3.1. The floppy controller may be disabled either in hardware via jumper Y20 (short) or in software with the EISA Configuration Utility.

If you were previously using Pre-release 1 reconfigure your DPT 2012 to the settings below before installing Release 3.1 for Intel Processors.

Jumper Settings
Y20 (Floppy Disabled): on (optional, factory setting: off)
Y19 (Option ROM Size): off (factory setting)
Y4(Factory Use Only): off (factory setting)
Y23(Firmware ROM Size): on (factory setting)

If the DPT 2012 will not be at the end of the SCSI bus follow the instructions provided with the DPT 2012 to remove the terminating resistors from the card. For more information on SCSI setup refer to NeXTanswer document1109_SCSI_Setup.rtfd

Use the EISA Configuration Utility (ECU) to set the following values.

ECU Settings
HARDWARE CONFIGURATION
Hardware Mapping
I/O Ports: Secondary/Disabled
Interrupt Number: 15 - Edge
Floppy Drive: Disabled
Option ROM: Enabled @ C8000h
HBA SCSI ID: 7

WD1003 EMULATION MAPPINGS
Drive 0
SCSI ID: Disabled
SCSI LUN: 0
Drive 1
SCSI ID: Disabled
SCSI LUN: 0

CONTROLLER PARAMETERS
SCSI Parameters
Maximum Transfer Rate: 5MB/s *
External Cable Detection: Yes - 5MB/s
Command Queuing: Enabled **
Command Timeout: Disabled
Cache Parameters
Cache: Enabled (Write-Through) ***
Max. Percentage Dirty: 80%
Max. Percentage Look-Ahead: 80%
Look-Ahead: Enabled (8 blocks)
Cache Threshold: 65535 blocks
Cache Parameters: Use Values Stored on Device

* 10MB/sec requires very good cabling and termination.

** Some SCSI devices do not correctly implement Command Queuing and require this feature to be Disabled.

*** See note in Known Problems regarding setting cache to "Enabled (Write-Back)."

(NeXT's Quality Assurance group tested using this EISA configuration file: !DPTA502.CFG Version: 005D)

Multiple versions of the ECU exist; other versions may present the configuration information in a different format. It should still be possible to match the settings detailed above. If problems are encountered refer to the documentation that came with the DPT 2012 or call DPT Technical Support for assistance.

Known Problems:

The default IRQ setting of 14 will cause the following error.
EATA controller at IRQ 14
Registering sc0

The system will then hang. To recover, use the ECU to reconfigure the non-volatile memory on the DPT card to select the proper IRQ. Unless you are sure that the right answer is something else, set it to IRQ 15, edge triggered. If your ECU diskette doesn't already have the files necessary to set up a DPT card, when you run the ECU and try to configure the card you will be prompted to insert the proper diskette from DPT . Once the card has been set to IRQ 15, your system will probably just boot. If it does not, at the "boot:" prompt, enter "mach_kernel config=Default" and the system will come up, allowing you to run Configure.app and set the DPT configuration to IRQ 15, edge-triggered. If you really do want to run it at something other than IRQ 15, now that the system is up you can do so - first use Configure.app to change the configuration to the new IRQ value, then use ECU to reconfigure the card, and you should be able to reboot and come up using the new IRQ. Remember though that if you do this, you will not be able to boot config=Default again unless you re-run ECU and set the DPT card back to IRQ 15.

Setting the Cache Parameters in the ECU to enable the cache in write-back mode may result in increased performance. However, any errors that prevent the cache from being written to disk before shutdown (power failure, system panic, etc.) could cause severe data loss.

	Up to 16MB of RAM cache
	33MB/sec EISA transfer
	EISA bus mastering
	SCSI-2 and CCS compliant
	10MB/sec SCSI sync transfer
	CAM-compliant EATA interface
	Overlapped commands
	Scatter/gather
	Automatic request sense
	RAID support in hardware

*	10MB/sec requires very good cabling and termination.

**	Some SCSI devices do not correctly implement Command Queuing and require this feature to be Disabled.

***	See note in Known Problems* regarding setting cache to "Enabled (Write-Back)."*

	The default IRQ setting of 14 will cause the following error. EATA controller at IRQ 14 Registering sc0

	The system will then hang. To recover, use the ECU to reconfigure the non-volatile memory on the DPT card to select the proper IRQ. Unless you are sure that the right answer is something else, set it to IRQ 15, edge triggered. If your ECU diskette doesn't already have the files necessary to set up a DPT card, when you run the ECU and try to configure the card you will be prompted to insert the proper diskette from DPT . Once the card has been set to IRQ 15, your system will probably just boot. If it does not, at the "boot:" prompt, enter "mach_kernel config=Default" and the system will come up, allowing you to run Configure.app and set the DPT configuration to IRQ 15, edge-triggered. If you really do want to run it at something other than IRQ 15, now that the system is up you can do so - first use Configure.app to change the configuration to the new IRQ value, then use ECU to reconfigure the card, and you should be able to reboot and come up using the new IRQ. Remember though that if you do this, you will not be able to boot config=Default again unless you re-run ECU and set the DPT card back to IRQ 15.

	Setting the Cache Parameters in the ECU to enable the cache in write-back mode may result in increased performance. However, any errors that prevent the cache from being written to disk before shutdown (power failure, system panic, etc.) could cause severe data loss.