Document # HW0001 Adaptec Host Adapter Hardware Commonly Asked Questions 3/93 Q. Why does my computer/SCSI HA think that I have 7 hard drives, (or CD-ROMs, or ..) when I only have one drive connected? A. When installing an Adaptec SCSI HA, SCSI bus protocol must be observed. The HA should be SCSI ID 7, always the highest ID number, so that the HA will always win SCSI bus arbitration. SCSI bus theory dictates that each device (the HA is a device) must have a unique and separate SCSI ID number. If a HD or other device is attached to the SCSI bus with the same ID as the HA, then the HA will see a response for "phantom" devices at IDs where no device exists. To solve this problem, simply set the devices ID to something other than that of the HAs SCSI ID. If the device is a boot drive, then the SCSI ID should be set at 0. The 152x/154xB/1640/174x (in standard mode) BIOS controls hard drives at SCSI ID 0 and 1 only. The 174x BIOS in enhanced mode will control hard drives at SCSI ID's 0 through 6. Hard drives or SCSI devices using ID's 2 through 6 need device drivers to be controlled using the 152x/154xB/1640 or 174x in standard mode. Q. Why can't I use the entire size of my hard drive that is rated over 1 Gigabyte in capacity, when I am using DOS? A. DOS 4.x and above has a limitation of 1024 cylinders per physical drive. This limitation, on current disk controllers and SCSI HAs that utilize the standard of 1 Megabyte per cylinder, leads to a 1 Gigabyte limit. Only our 1542B/GIG and 174xA (with special BIOS in Enhanced Mode using ASW-C174 v3.1) have the ability to break this limit. If your 154xB has a BIOS part number of 420418-00D or greater, or if your 174xA has a BIOS part number of 450216-00-A or greater, then you already have support for more than 1 Gigabyte. Refer to your User's Manual addendum for help on setting up this feature. Alternatively users who need this support can download the latest 154xB or 174x microcode/BIOS files from this BBS for use with an EPROM burner. The EPROMs needed are 27C128 at 200ns for the 154xB and 150ns for the 174x. 154xC boards come ready to support hard drives larger that 1 Gigabyte. Q. Why can't I use my new CD-ROM/Tape/WORM drive with my Adaptec HA? A. Most Adaptec SCSI HAs are designed to support two HDs and on some models 2 floppy drives with just a bare board. Additional devices require the use of a device driver. For more information on what your particular HA/kit should support, contact your dealer/distributor or look at KITS.TXT on this BBS for an overview. Spec sheets are available on Adaptec's Interactive FAX system. Q. Why when I boot do I see a message that says something like "SCSI BIOS not installed", or I see a message that says "Drive C already installed" or "Searching for Target 0" and my computer hangs here for about 60 seconds before going on? A. The BIOS on Adaptec HAs is used primarily for booting off of attached SCSI HDs set to ID 0 (Target 0). SCSI ID of the HD is set with jumpers or switches located on the HD. If the HA you are using is not being used to control a bootable SCSI HD, and the HA has been working with the attached devices and their associated drivers, then disable the BIOS on the HA you are using. Consult your HA User's Guide, or Installation Pamphlet for the jumper that enables the BIOS, or the software switch that needs to be set to disable the BIOS. 152x and 154x boards can have the BIOS disabled with jumpers, 1640 and 174x boards BIOS' enabling is controlled by software. The 154xC board's BIOS address is controlled by DIP switched located at the top edge of the board. Q. Why does my 174x board always come up in the configuration as being in Standard Mode, and what is the difference between Standard Mode and Enhanced Mode? A. The default of the configuration files and overlay files used to configure the 174x is the most compatible mode, Standard. Standard Mode is equivalent to 154x emulation. Standard Mode requires IRQ, DMA and I/O port definitions and policing by the installer. Only 4 174x's can be used if all are in Standard mode because of the number of available DMA channels for use in this mode. Enhanced Mode allows the installer the luxury of not having to worry about the DMA, IRQ and I/O address, as this is all taken care of by the configuration and EISA motherboard. Enhanced mode also is the only mode that supports Fast-SCSI (up to 10 Meg/sec. and 32 bit addressing). Up to 4 Gig of RAM is supported, with up to 12 HAs being allowed, with the limit being imposed by the number of EISA slots. Standard BIOS supports 2 hard drives with support for more hard drives or other device types coming from device drivers. Standard BIOS requires the use of ASPI4DOS.SYS for DOS ASPI management. Enhanced BIOS supports up to 7 hard drives of up to 8 Gigabyte each, with support for other devices coming from device drivers. Enhanced BIOS requires the use of ASPIEDOS.SYS for DOS ASPI management. Support for drives grater than one Gigabyte can only be achieved with 174x BIOS part number 450216-00A or greater with the ASW-C174 version 3.1 configuration files, available on this BBS in the file called ASWC174.EXE. As with any Adaptec host adapter, hard drives controlled by the BIOS need to be partitioned with DOS's FDISK for use with DOS. Q. Why can't I configure my 174x in Enhanced Mode, seeing the EISA motherboard error "ID mismatch in slot X", or why do I always see the error "Host Adapter Initialization Failed!" when I configure the card for Enhanced Mode? A. As the EISA standard evolved, the differences between different manufacturers propagated. The 174x family of boards are well designed, high performance boards that need some special attention to get them installed in a few EISA motherboards. Some of the Adaptec Technical Support situations that have occurred include: 1) When using the AMI ECU program, the installer should verify that they are using version 1.4C or higher of that ECU program. When using this ECU program, the installer should verify that they are using the correct CFG file needed for their type of 174x board, and that the file ADP0000.OVR (dated 6/4/92) exists in the same directory that the ECU program and CFG files are in. When using the AMI ECU program earlier than 1.4C, the installer will not be able to configure the board in Enhanced Mode, using the ASW-C174 utilities v3.0 or later. To configure the 174x, put the appropriate !ADPxxxx.CFG file from the ASW-C174 configuration set into the same directory that the CFG.EXE program is run from. The files are: !ADP0000.CFG AHA-1740 (no letter) !ADP0001.CFG AHA-1740A or AHA-1742A w/floppy disabled !ADP0002.CFG AHA-1742A !ADP0400.CFG AHA-1744 Also, in the same directory, be sure that the ADP0000.OVR file exists. 2) When using some Compaq DeskPro, SystemPro, or similar computers that have the CPU mounted on a special board, the installer should take care to minimize the number of boards between the CPU board and the Adaptec 174x board. It seems that when other EISA boards exist between the Adaptec HA and the CPU board, the Enhanced Mode configuration will not complete, or the board will report an error indicating that the HA could not be initialized. This seems to be a situation that is not consistent, and is usually only associated with EISA communication boards in the slots between the HA and CPU boards. 3) It seems that some 50Mhz and faster motherboards have increased the response time of the INT signal from the adapter cards. If your 50MHz or faster EISA motherboard gives you the error "Failed to Initialize Host Adapter" after configuring it for Enhanced Mode, then follow these steps. Using a DOS editor, open the CFG file (it's ASCII text) being used. Somewhere around line 120 you will see a line that reads "CHOICE = ENHANCED MODE". Under this a few lines will be the line "TRIGGER = EDGE" or "TRIGGER = LEVEL". If this line says EDGE, change EDGE to LEVEL, this is the standard setting for MOST EISA motherboards. If it says LEVEL, then try using EDGE. WARNING!!! This fix has only been used in less than one percent of the cases, so don't use this as a catch all fix. The recommended and default setting is LEVEL.