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Adaptec 1542 ISA SCSI Card
SCSI (pronounced "Scuzzy") card uses certain resources of your computer's system in its operation. This card uses the Input/Output Range (I/O), BIOS Address, Interrupt Request (IRQ), and Direct Memory Access Channel (DMA). A depth of understanding of these terms is unnecessary to install the card. All that is necessary is the practical knowledge of how and when to change these values, which is explained below.

The 1542 card is an ISA card. It is inserted into a black ISA expansion slot on the motherboard. If you do not have an available ISA slot, or only have white PCI slots, please contact Academy to upgrade your card.

These instructions are for adding the 1542 to a Windows 3x / 9x computer. Use these links for assistance adding a SCSI card in a Novell Server or NT Server.

Determining Resource Settings
Windows 3x
There is no "wizard" or program to help you determine what resources are free to assign to the card. In most cases, no changes of DIPswitch or firmware settings are necessary. The default settings of I/O Range 330, BIOS Address DC000h, Interrupt Request 11, and Direct Memory Access Channel 5 will work with most basic computers. If these default settings do not work, several methods can help reduce the guesswork of determining the correct settings.

Check any documentation for the computer and card already installed. Many cards have installation utilities that can help establish the current settings of that card. For example, C:\SB16\WINAPPL\CTCONFIG.SYS will invoke the Sound Blaster sound card configuration utility (if present in Windows 3.1).

Use diagnostic software. The Microsoft Diagnostic Program (MSD.EXE) is in DOS 6.22, as well as Windows 3.1x. To start the program type C:\DOS\MSD.EXE at the C:\ prompt. This program cannot detect cards added after the system was initially designed, but it will provide a beginning for the process of determining the correct settings.

Remove all non-essential cards from the system. Configure and install the Adaptec 1542 card. Add the remaining cards one by one. When a conflict occurs, change the settings of the last card added.

Use the Trial-and-Error method. Try different settings of the Adaptec 1542 card, and reboot after each trial. Be sure to record which setting combination you have tried.

Windows 9x/ME
You determine the correct hardware settings under Windows 9x/ME by using the Add New Hardware Wizard. Use the steps below to determine the correct card settings for your computer:

  1. Double-click on My Computer
  2. Double-click on Control Panel
  3. Double-click on Add New Hardware
  4. Click on Next.
  5. When asked, "Do you want Windows to search for your new hardware?" click NO, then Next.
  6. Select SCSI Controllers, then Next
  7. Select Adaptec AHA-154X/AHA-164X SCSI Host Adapter, not the Plug and Play version above it.
  8. Write down the recommended configuration for the card. If instead of hardware settings the message "You are using other hardware that conflicts with the hardware you are trying to install." appears, you must reallocate some system resource(s).
  9. Click on Cancel.
  10. Shut down the computer and disconnect the power.

Input/Output Range (I/O)
In the upper left hand corner of the card is a block of eight (8) switches. Switch 1 controls plug-and-play. Caveat Emptor. In order to change any setting on the card, switch 1 must be turned on, which defeats plug-and-play. Turning a switch "On" means pushing the switch toward the card. "Off" points away. Switches 2 through 4 control I/O range. Switch 5 controls the floppy, which is defeated at the factory by switching it "on" or toward the card. Switches 6 through 8 control the BIOS address, and are normally not altered except in multiple card installations.

I/O Range Switch 2 Switch 3 Switch 4
130 Off Off On
134 On Off On
230 Off On Off
234 On Off Off
330 (default) Off Off Off
334 On On Off

If the I/O range of the AHA-1542CP card conflicts with the I/O range of other cards, the following symptoms will occur:

No echo of the card will appear on the screen directly after the memory test.

Hardware Timeout Reset Error appears on the screen early in the boot process.

The system freezes (becomes unresponsive) early in the boot process.

BIOS Address
BIOS address conflicts are rare except when more than one AHA-1542 card exists in a given computer system. Then each card must have a unique BIOS address. BIOS address is set via dip switches on the same Switch Block as the I/O Range area. For BIOS address adjustment, use switches 6, 7, and 8

BIOS Address Switch 6 Switch 7 Switch 8
DC000h (default) Off Off Off
D8000h On Off Off
D4000h Off On Off
D0000h On On Off
CC000h On Off On
Disabled On On On

If you choose to disable the BIOS using these switch settings the Adaptec 1542 SCSI card will no longer echo/broadcast during the boot process. This is to be expected. You may disable the BIOS using the SCSISelect utility instead. The Advanced Configuration option of this utility will allow the BIOS to be disabled without preventing the card from echoing. If this firmware choice is made, the SCSI devices attached to the card will not echo, but the card will.

Direct Memory Access (DMA)
DMA channel is changed by entering the SCSI select utility. Press Control-A when prompted. Then press Enter twice to reach the screen where DMA channels can be altered. Change the DMA channel by placing the cursor at the box to the right of the DMA channel label, press Enter, select the desired value using the up and down arrows. Press Enter. Save the changes by pressing the escape key (ESC) and following the prompts. Repeat this procedure using different values for the DMA channel: 0,5 (default), 6,7 until the system appears to be functioning normally.

If the message Press Control-A for Setup appears, but the system stops during bootup, the problem is usually a DMA conflict.

Another message that indicates DMA conflict is Unable to enable/disable shadow RAM.

Finally, if this is a multimedia computer, a buzzing sound from one of the speakers can indicate a DMA conflict. DMA 5 is used by sound cards and is the default for the AHA-1542 card.

Interrupt Request (IRQ)
The SCSISelect utility is accessed by pressing Control-A during system bootup. Then press Enter twice to reach the screen where IRQ channels can be changed. Possible IRQ settings are 9,10,11 (default),12,14, and 15. Follow the directions on the screen to save and exit.

If one but not all of the components of your system become inoperable after installing the AHA-1542CP, the culprit is usually an Interrupt Request. For example, the system might run smoothly except for the mouse, modem or network card. Change the IRQ to 10 or 12 by entering the SCSI select utility. IRQs 14 and 15 are usually reserved for the Primary and Secondary Hard Drive Controllers (i.e. the hard drive of the computer). Only use these IRQs if you are sure that neither is in use.

Error Messages
Error messages that occur during bootup have limited direct meaning; rather they are best viewed as a code that indicates a possible problem.

When You See It usually means.....
ASPI4DOS installation failed Drives undetected due to I/O, IRQ or DMA conflict.
BIOS not intended to run this card I/O conflict
Hardware Timeout Reset Error I/O conflict
No SCSI devices are found Loose cabling or IRQ conflict
The computer is unresponsive after Press Control-A for SCSISelect Utility appears Most likely DMA conflict, but may also be other resources
Unable to Enable/Disable Shadow RAM DMA conflict

Conflict Free Card
If all of the Adaptec 1542 SCSI card settings are conflict free, during the system boot (i.e. after you turn the computer on) you will see a setup message where the <brand> and <model> designations below are replaced by the brand and model of the CD-ROM drives in your tower.

Adaptec AHA-1540CP/1542CP BIOS V.1.02
(c) 1995 Adaptec, Inc. All Rights Reserved.
Press Control-A for SCSISelect(TM) Utility!
SCSI ID #0  <brand>CD-ROM  <model>
SCSI ID #1  <brand>CD-ROM  <model>
SCSI ID #2  <brand>CD-ROM  <model>
SCSI ID #3  <brand>CD-ROM  <model>
SCSI ID #4  <brand>CD-ROM  <model>
SCSI ID #5  <brand>CD-ROM  <model>
SCSI ID #6  <brand>CD-ROM  <model>
 

The message above will appear for a seven bay Tower. A 14 bay will show this twice. The setup message for the four bay tower will list SCSI ID numbers 3 through 6. The message Waiting for SCSI ID #0 may display for 2-3 minutes, but requires no response.

Click here for help with installing the software drivers.