Here are the latest (930125) release drivers for Adaptec host adapters
and OS/2 2.X. 

 AHA152X.ADD    23535   1-25-93  17:31
 AHA154X.ADD    19351   1-25-93  16:47
 AHA164X.ADD    18759   1-22-93  10:35
 AHA174X.ADD    16771   1-25-93  16:48

The major enhancement of these drivers over the 12/92 versions that are now
included with the OS/2 2.1 beta is more information from /V.

Bug fixes:
        1) Parameter parsing does not always get handled correctly when the
        adapter is not at the default port address. These new drivers will
        correctly handle parameters for adapters at any port address.

Command line switches for Adaptec drivers and OS/2 2.0

OS/2 adapter device drivers (.ADD files) are normally installed automatically 
and require no further information from the user. However, in certain situations 
the user may wish to modify the behavior of the driver to meet their specific 
needs. 

***** IMPORTANT *****
Please proceed cautiously with the following information. If you have purchased
software which requires you to use switches, it should include instructions
on how to use them. Most software requires no switches and you do not need to
concern yourself with the information about switch settings.

The following examples will all use the driver for the Adaptec 1542B, but the 
driver for any other Adaptec host adapter can be used instead.

The standard format for command line switches is :
BASEDEV=AHA154X.ADD  [Universal Parameter] 
                     [Adapter ID] [Unit Parameter] {: [SCSI Target ID]}

[Universal Parameter] - An option that applies to all adapters controlled by 
                        the driver.

[Adapter ID] - /A:n, 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).

	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.

	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.
        
Driver Specific Information

AHA152X.ADD
This driver can support two host adapters and searches for them at ports 340H 
and 140H; boards are assigned adapter numbers in the order they are found.

      Universal Parameters
	/SN - Allow synchronous negotiation (DEFAULT).
	/!SN - Prevent synchronous negotiation.

      Special Unit Parameters

        /D - Allow targets to disconnect from the SCSI bus (DEFAULT).
        /!D - Prevent targets from disconnecting from the SCSI bus.

        /H:x - Specifies the host adapter SCSI ID. A number from 0-7 replaces 
        x. The default ID is 7. If you specify an invalid number, the default 
        is used.

*** IMPORTANT
        /Q:x is NOT supported anymore. All interrupt assignments are found by
        scanning IRQs 9-12.

        /Y - Enable parity checking on the SCSI bus (DEFAULT).
        /!Y - Disable parity checking on the SCSI bus.

AHA154X.ADD
This driver can support four host adapters, distributed among six possible 
port addresses. The port addresses are scanned in the order 330H, 334H,
230H, 234H, 130H, 134H; boards are assigned adapter numbers in the order 
they are found.

        Special Unit Parameters (09/19/92 and later )

        /BON:t - allows the bus-on time to be set to a value between 2 and 15 
        microseconds. The default value for OS/2 2.0 is 7 microseconds and 
        this value should be used for most systems. 

        /D - Allow targets to disconnect from the SCSI bus (DEFAULT).
        /!D - Prevent targets from disconnecting from the SCSI bus.
        *** This command is not supported on boards earlier than revision B.


AHA164X.ADD
This driver can support host adapters installed in any 16-bit MCA slot. The 
slots are scanned from lowest to highest and boards are assigned adapter 
numbers in the order they are found. The slots are scanned twice, the first 
scan will find all boards with their BIOS enabled and the second will find 
those with their BIOS disabled.

AHA174X.ADD
This driver can support host adapters installed in any EISA slot. Adapter 
numbers are first assigned to boards with their BIOS enabled; the numbers are 
assigned from lowest BIOS address to highest address. Any remaining boards are 
assigned adapter numbers by scanning the slots from lowest to highest and 
boards are assigned adapter numbers in the order they are found.
