CONNECTING ADDITIONAL DEVICES TO YOUR SYSTEM (DAISY- CHAINING) You can attach additional Small Computer Standard Interface (SCSI) devices to your system by plugging them into the back of your external SupraDrive or Amiga 2000 interface. This practice is sometimes called "daisy-chaining." The SCSI devices you might connect include laser printers, Bernoulli boxes, optical disk drives, streaming tape drives, and other disk drives. (Note that to use these devices you must also have appropriate supporting software from the device manufacturer.) Before daisy-chaining SCSI devices, first make sure that each device you plan to include in your daisy chain functions properly by itself, and then make sure that all the devices have SCSI numbers and LUNs that will work. Making Sure Your Devices Have SCSI Numbers and LUNs That Will Work What Interfaces, Controllers, and Disk Drive Are In addition to the Supra SCSI Interface, every SupraDrive includes the drive itself and a controller to run the drive. Note the important distinction between an interface and a controller. An interface allows a controller and drive (on the one side) to connect to a specific computer (on the other side), and a controller actually controls the disk drive. For an external SupraDrive, the interface is in one case, and the drive and controller are inside the second case. The controller is either a small card attached to the drive or built into the drive. For an internal SupraDrive, all the SupraDrive components are inside the computer. The interface is one card, and the controller either is a small card attached to the interface or it is built into the disk drive. What SCSI Numbers and LUNs Are Each drive and each controller has its own identification number -- SCSI numbers represent the controllers, and logical unit numbers (LUNs) represent the drives. You can have as many as seven SCSI controllers, numbered from SCSI 0 to SCSI 6. (In Supra systems, SCSI 7 is reserved). You can also have either one or two devices connected to each controller (the specific controller determines the number of devices that can be connected). If you have one device connected to a controller, the device is LUN 0; if you have two devices connected to a single controller, the devices are LUN 0 and LUN 1, depending on the plug they are attached to. Determining Your Devices' SCSI Numbers and LUNs When shipped, SupraDrives are configured as follows: ­ SupraDrive hard disks are SCSI device 0, and add-on SupraDrive hard disks are SCSI device 2. (An add-on SupraDrive is one that is shipped from Supra to be used as a second (or third) peripheral in a daisy-chain. You do not have an add-on SupraDrive unless you specifically requested one.) ­ All SupraDrives are set to LUN 0. If a device you want to connect is made by another company, refer to the product manuals or contact the company to learn what the product's SCSI number and LUN are. Do You Need to Change Your Devices' SCSI Numbers or LUNs? LUNs It is very unlikely you will need to change your LUN numbers. If you think you need to change a LUN number on a Supra product, please contact Supra Technical Support for assistance. SCSI Numbers For more than one SCSI device to be connected to the same system, each device must have its own SCSI number. For example, if you want to connect two SupraDrives, you'll need to be sure they aren't both set to be SCSI 0. If they are, you'll need to change one of their SCSI numbers. If all the devices you want to use have different SCSI numbers, you can skip the next few sections and simply connect the devices as described later in this section. If any of the devices you want to use have the same SCSI device number, you need to change the SCSI number of one of them. The next section explains how to do this. Changing a SCSI Device Number There are different ways to change a SupraDrive's SCSI device number, depending on type of drive. ­ If your drive has a SCSI device number selector on its case that allows you to select a number between 0 and 7, you can simply change the drive's SCSI number by turning off your system, using the SCSI device number selector to select the desired SCSI number, and then rebooting your system. ­ If your drive does not have this switch, follow the steps below. ­ If you have an internal SupraDrive, follow the steps below, but ignore the instructions for removing and then replacing the SupraDrive case. If you want to change a SCSI device number on a device made by another company, get instructions from that company and follow them carefully. The rest of this section explains how to change a SCSI device number on a SupraDrive that does not have a SCSI device number selector on its case. We recommend reading the entire procedure before actually performing the steps. 1. Get a Phillips screwdriver and a pair of needle nose pliers, and make sure the SupraDrive you're going to change is UNPLUGGED and NOT CONNECTED to a computer. If you have an internal SupraDrive, remove the interface, controller, and hard disk from the computer. 2. Find the label on your SupraDrive that says what brand of drive mechanism it uses. Some of the possible drive mechanisms are Miniscribe, Rodime, Seagate, Xebec, Quantum, and Konica. 3. Note that the following files (and possibly others) came with your SupraDrive. Both files contain pictures of the controllers for the different drive mechanisms used in SupraDrives. Controller_1.pic Controller_2.pic 4. Use CLImate to look at the files and find the picture of your drive's controller, as follows: a. Open the Supra drawer. b. Click on the CLImate icon. c. Select the drive that holds the Supra drawer. d. Open the Supra drawer, and then open the pics drawer. e. Click on the the Showpic gadget. f. Select the file you want to look at, and the file will open. g. Look for your controller's picture. h. If the picture is not in the first file, press the left mouse button to close the first file, and then look at the second file. g. You probably want to leave the file that contains your controller's picture open until you are done changing your SCSI device number. When you're done looking at the file (now or later), press the left mouse button to close it. h. When you're ready to quit CLImate, click on Quit. 5. If you have an external SupraDrive: Unscrew the screws that hold the SupraDrive case together, and then carefully remove the top part of the case, being careful not to pull the indicator lights out of the front of the case. Set the case top down on the table. Inside the case, you'll see the drive mechanism. If you have an internal SupraDrive: Skip this step. 6. If you have an external SupraDrive: You'll see at least one circuit board mounted on top of the drive mechanism. The circuit board that is on the very top is the connector board. Note: As you remove the connector board, pay attention to how it attaches. You'll need to replace it later. Unscrew the screws that hold the connector board to the components underneath it, and, without unplugging any cables, carefully remove the connector board and set it aside. If you have an internal SupraDrive: Skip this step. 7. Locate the drive's controller as follows. If you have an external SupraDrive: The controller is on top of the drive. If you have an internal SupraDrive: The controller is either a small board mounted on the SupraSCSI Interface, or it is built into the hard disk (meaning you have an integrated drive). If you have an integrated drive and you have a hard card that doesn't allow you access to the drive's controller, remove the drive from the interface. 8. Compare the controller with the picture of the controller. Move the SupraDrive as necessary so you can look at the picture and controller from the same perspective. 9. Find the SCSI selector marked in the picture, and then find the actual SCSI selector on your drive's controller. The SCSI selector is a "header." The actual number of pins may vary between six and sixteen. The SCSI device number is determined by the location of rectangular "jumpers" that connect the header's pins. 10. Set the SCSI device number by placing jumper(s) across pins as shown below. (You might need to use needle nose pliers to do this.) If you need more jumpers, you can get them from a local dealer. Note that each jumper covers two header pins. To help you determine which set of two pins to use, the sets are labeled in the tables below and in the diagrams in the files. To create the diagram, a colon ( : ) is used to represent a set of open pins. A bar ( | ) represents set of pins that have been jumped. SCSI # Pins 1 2 3 0 : : : 1 | : : 2 : | : 3 | | : 4 : : | 5 | : | 6 : | | 7 | | | 11. If you have an external SupraDrive: Replace the connector board you removed earlier (in step 6), and replace the SupraDrive case top. If you have an internal SupraDrive: If you removed the drive from the interface, replace it. 12. You're done changing the SCSI device number. Now you can connect your system as described in the next section. Connecting the Devices To connect additional devices, follow the steps below. Note that no matter how many devices you connect, you need only one Supra SCSI Interface. 1. Make sure your computer and all the devices you plan to connect to it are turned off. 2. Install your SupraDrive as described in the SupraDrive Operator's Manual. 3. Plug your second device into the SCSI port on the back of the SupraDrive or Supra SCSI Interface. 4. If the second device has a SCSI output port, you can connect a third SCSI device to the second. If you want to, you can continue daisy-chaining devices until you have seven devices connected to your system. 5. Connect all the devices to power. 6. Note that you may need to change any assignments you've made using the Assign command to correctly reflect your new setup. (Remember that changing the SCSI ID numbers can affect the start- up sequence.) The SupraDrive Operator's Manual explains how to use the Assign command and the start-up sequence. If you have problems, try the following: 1. Make sure all your cables and connections are complete and secure. 2. Note that for some devices, the order in which the devices are connected affects the order in which the devices must be powered up. Due to the large number of possible device combinations, Supra Technical Support is not able to tell you what order will work for your devices. To determine which order will work for you, experiment. 3. Consider changing a devices' "termination," although this is a rare problem. Unfortunately, due to the large number of device combinations available, Supra Technical Support is not able to tell you how termination should be set for your daisy-chain. If you suspect termination might be the problem, please contact your dealer for assistance.