original date 10/29/1989 How to get more than two hard disks on your system. What I used: 1 Western Digital 1002-27X RLL controller w/SUPER Bios Formatter ROM 1 Western Digital 1002-WX1 MFM controller w/SUPER Bios Formatter ROM 2 NEC D5126 30 MB RLL Hard Disk 2 Seagate ST225 20 MB Hard Disk 1 Disk Manager 3.1 by Ontrack Computer Systems, Inc. NOTE: DON'T USE VERSION 3.2 I recently added two more twenty megabyte hard disks to my system to compliment my exsisting two 30MB RLL drives. I did not want to buy another large capacity drive. I wanted to make use of some drives I had lying about from previous upgrades. Well, what is a person to do? It is a known fact that DOS can only see two drives attached to any system using using an ST412 Interface, the standard run of the mill type of controller. The use of certain device drivers bypass the ROM and DOS routines for looking at drives attached to the system. Uilizing these device drivers allows one the use of three or four ST412 type drives. I will outline the procedure as follows. To connect four drives, you need two controller cards. I used two by Western Digital, a 1002-WX1 and a 1002-27X. The latter of which is an RLL type. I suggest reading the documentation with the controllers in order to set the jumper switches for your particular drive. I recommend the use of Western Digital controllers due to their high reliability factor and support. The Western Digital controllers MUST have the Super BIOS Roms on them. Others may not work properly. I tried DTC type controllers and found that the ROM routines on the controllers would not allow two to coexist properly in the same machine. You will also need a copy of Disk Manager by Ontrack Systems. I don't know the extent of this, but version 3.2 did not work on my system. I used version 3.1 without a hitch. The first step is to set the ROM and I/O addresses for each of the con- trollers. Select which controller you would like to use as the first one. I chose the RLL controller to be my "boot" controller. I will here out refer to the RLL controller as controller 1 and the standard controller as controller 2. Since these boards are relatively similar, the jumper settings are also similar. Western Digital provides two jumpers to change the addresses of the controllers. These are refered to as W4 - Device address and W8 - controller ROM address. The default configuration, and the one to use for controller 1, should be W4 jumpered on pins 2 and 3 (320H) and W8 jumpered on pins 2 and 3 (C800). Connect the drives as you normally would for a single controller system. (Refer to bulletin #34 Installation using 1002-WX2 controllers). Next, take controller 2 and configure it with jumper W4 using pins 1 and 2 (324H) and W8 using pins 1 and 2 (CA00). Again connect the two drives as you normally would for a single controller system. The next step is to install the two cards into the machine and boot the system. A long wait and a few errors may occur if they are new drives that are not prepared yet. After the system is booted, put your disk with DEBUG.EXE on it into the drive. Run the program, and at the "-" prompt, type "G=C800:5 " less the quotes. You will need to repeat this step for each drive, c: d: e: f:. It prompts you for the drive. Use it's recommended interleave factor for now. You can play with that one after you know it is working. Follow the controllers directions for this initialization process. When finished, you will need to get out your Disk Manager Disk by Ontrack Data Systems. Run Disk Manager in manual mode and create a partition on each of the hard disks. Do not use FDISK to do this. Disk Manager writes specific stuff to the disks in order to find them. Set up the first disk and partition as a "DOS" type partition and the other three as "WRITE/READ" partitions. Next, you must prepare each partition using Disk Manager. This does a DOS type format. DONT USE YOUR DOS'S FORMAT UNLESS YOU HAVE TO. After all four drives have been partitioned and prepared for use, you should be ready to boot up again. This is where the first headaches start to come in. My system is run on a Leading Edge Model D. After using Disk Manager, I was unable to boot even from a floppy. It would crash while reading in the system files. I tried many, at least a dozen, different versions of DOS from many different machines. As it turns out, I had to use a DOS which had compatibility software written into it. I did not want to use DOS 2.11 which came with my system so I purchased a copy of AST DOS 3.2 which did the trick. I suspect that those with IBM's will not have a problem. At this point, when you boot your system from the DOS disk, you should only be able to get to drive C:. Follow Disk Managers instructions to install their device driver DMDRVR.BIN into your config.sys file if not already there. Next time you boot your system, it should look at all four drives as it loads the device driver. You should now get access to c: d: e: and f:. If you have any problems, I will be more than willing to help you out. Listed below are some numbers and addresses you may find useful. Good luck. Ontrack Computer Systems, Inc. 6222 Bury Drive Eden Prairie, MN 55344 Product info: 800-752-1333 Tech support: 612-937-2121 Western Digital 2445 McCabe Way Irvine, CA 92714 Tech Support: 800-847-6181 Seagate 920 Disc Drive Scotts Valley, CA 95066-4544 Product Info: 800-468-3472 Blaine Korcel DATA: 703-256-4777 NOVAC RBBS 2400 BPS VOICE:703-256-4430 6PM-10PM EASTERN