AHA174X.ADD

Product Support
OS/2 1.3
OS/2 2.0	S
OS/2 2.1	S
OS/2 2.11 SMP	S
OS/2 Warp 3	S
OS/2 Warp Connect	S
OS/2 Warp 4	S
OS/2 Warp Server for e-Business	S

Driver for the Adaptec AHA-1740/1744 EISA SCSI host adapters.

Syntax

BASEDEV=AHA174X.ADD <parameter>

BASEDEV=AHA154X.ADD /A:n [Unit Parameter] {: [SCSI Target ID]}

Parameters

[Universal Parameter]

An option that applies to all adapters controlled by the driver.

/A:n

Adapter ID. Where n is the number (zero relative) of the adapter installed in the system. The adapter ID is determined when the driver is loaded based on the order that adapters are found in the system.

Please refer to the section on each host adapter to determine the scanning order.

[Unit Parameter]

The modification being made to the behavior of the selected host adapter.

[SCSI Target ID]

The targets to which the Unit Parameter will be applied. This parameter may be and single ID (d) or list of IDs (d,d,d).

Universal Parameters

/ET

Allow embedded targets. This parameter indicates that the ADD should assume that all targets have more than one logical unit (LUN) defined.

/!ET

Do not allow embedded targets (DEFAULT). This parameter indicates that the ADD should assume that all targets have only one logical unit (LUN) defined.

/V

Load driver verbosely. This parameter will display the driver name as well as the version number and Adaptec copyright if the driver loads successfully. Information on all targets found in the system will also be displayed. This switch is only valid in drivers dated 11/24/92 and later.

General Unit Parameters

/DM

Enable DASD manager support (DEFAULT). This parameter allows OS2DASD.DMD to control the specified target(s) if they are identified as DASD devices.

/!DM

Disable DASD manager support. This parameter prevents OS2DASD.DMD from controlling the specified target(s).

/SM

Enable SCSI manager support (DEFAULT). This parameter allows OS2SCSI.DMD to control the specified target(s) if they are identified as NON-DASD SCSI devices. All SCSI hard drives will be controlled by OS2DASD.DMD.

/!SM

Disable SCSI manager support. This parameter prevents OS2SCSI.DMD from controlling the specified target(s).

Examples

Example 1

Suppose that you had a removable hard drive as target 3 and you wanted to control the hard drive with an ASPI application and driver. Normally OS2DASD will allocate this device, treat it as a large floppy and prevent you from sending any SCSI commands via ASPI.

BASEDEV=AHA154X.ADD /A:0 /!DM:3 will prevent OS2DASD.DMD from accessing the target and still allow OS2SCSI.DMD and OS2ASPI.DMD to share access to it.

Example 2

Suppose that you had a CD-ROM as target 4 on host adapter 0 and two DASD devices as targets 1 and 5 on host adapter 1.

BASEDEV=AHA154X.ADD /ET /A:0 /!SM:4 /A:1 /!DM:1,5 will prevent OS2SCSI.DMD from accessing the CD-ROM and prevent OS2DASD.DMD from controlling the DASD devices. The driver will also search for multiple LUNs on all host adapters.

Remarks

Important Tips

1)There are no switches for controlling OS2ASPI.DMD directly. IBM did not define them in their specification and we cannot be sure that other host adapters will have the same switches.

2) OS2SCSI.DMD will only allocate devices when a device drivers requests it, but this will prevent OS2ASPI from accessing it. There is nothing in the ASPI specification regarding device allocation so OS2ASPI must rely on other managers to fairly share targets. This should only be a problem if you have two drivers that use different managers and you want them both to access the same target at the same time.

3) Do NOT disable DASD manaager access to target 0 if you are booting from your SCSI host adapter. This will prevent the system from booting.

Links

• Adaptec_AHA174X_1994-05-10.zip (1994-05-10)