READ THIS FIRST INSTALLATION GUIDE WD1004-27X WD1004A-27X Winchester Disk Controller Boards FEBRUARY 1989 COPYRIGHT 1989 WESTERN DIGITAL CORPORATION ALL RIGHTS RESERVED INFORMATION FURNISHED BY WESTERN DIGITAL CORPORATION IS BELIEVED TO BE ACCURATE. HOWEVER, NO RESPONSIBILITY IS ASSUMED BY WESTERN DIGITAL CORPORATION FOR ITS USE; NOR FOR ANY INFRINGEMENT OF PATENTS OR OTHER RIGHTS OF THIRD PARTIES WHICH MAY RESULT FROM ITS USE. NO LICENSE IS GRANTED BY IMPLICATION OR OTHERWISE UNDER ANY PATENT OR PATENT RIGHTS OF WESTERN DIGITAL CORPORATION. WESTERN DIGITAL CORPORATION RESERVES THE RIGHT TO CHANGE SPECIFICATIONS AT ANY TIME WITHOUT NOTICE. Radio Frequency Interference Statement This Western Digital product has been verified to comply with the limits for a Class B computing device pursuant to subpart J of Part 15 of FCC rules. This does not guarantee that interference will not occur in individual installations. Western Digital is not responsible for any television, radio, or other interference caused by unauthorized modifications of this product. If interference problems do occur, please consult the system equipment owner's manual for suggestions. Some of these suggestions include relocation of the computer system away from the television or radio or placing the computer AC power connection on a different circuit or outlet. This digital apparatus does not exceed the Class B limits for radio noise for digital apparatus set out in the Radio Interference Regulations of the Canadian Department of Communications. If you require further information or other technical support, please contact your authorized dealer: ************************************************************************** INTRODUCTION ************************************************************************** The WD1004-27X and WD1004A-27X boards are easy to install. The following is a summary of the installation steps. 1. Preliminary: set jumpers, drive configuration 2. Install hardware: drive, board, connect cables 3. Install software: use debug, low level format, etc. 4. Check installation: start system, use new board & drive CAUTION Handle the controller board by the ends of the board. Some of the chips are static sensitive and damage may occur if the board is incorrectly handled. ************************************************************************** ABOUT THIS GUIDE ************************************************************************** Angle brackets < > refer to a key. Therefore the symbol refers to the Enter key. This guide was written using the IBM* XT computer as a model. Sometimes specific examples, such as errors, refer to the IBM error code numbers. Therefore if you have an XT compatible computer, your error numbers may be different. About Menu Screens: Because computer manufacturers are always updating their products, and this installation guide covers installing both WD1004-27X and WD1004A-27X controller boards in many XT compatible computers, some of the menu screens may not be exactly the same on your system. Always follow the instructions on your computer screen. * IBM is a registered trademark of International Business Machines Corporation. 1 SOME PRELIMINARY STEPS Before you begin the actual installation of the hardware and software, there are some preliminary steps that you need to do. ************************************************************************** GATHER SUPPLIES ************************************************************************** The installation requires that you gather the following tools and supplies. - screwdriver - XT compatible computer with space to hold the internal drive - RLL hard disk drive(s)<187>with ST506 interface - interface cables (20-pin data cables & 34-pin control cable) - DOS version 2.0 or later (DOS 3.1 or later recommended) - installation manual for XT compatible computer - installation manual for hard disk drive ************************************************************************** IDENTIFY DRIVE ************************************************************************** The WD1004-27X and WD1004A-27X boards work with any hard disk drive that has the ST506/412 drive interface and no more than 1024 cylinders and 16 heads. The Seagate 238 hard disk drive unit is such a drive. Look in your drive manual to verify that you have an ST506/412 RLL drive or check with your dealer. Then check the drive manual for the drive parameters, such as those listed in Table 1-1. You'll need this information to select the proper low level format. Table 1-1. WD1004 and WD1004A Default Drive Parameters ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Formatted Capacity Number of Heads Number of Cylinders Sectors per Track 32MB 4 615 26 ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ This board works with RLL drives. If you have an MFM drive you should use the WDXT-GEN2 or WD1004A-WX1 board. ************************************************************************** IDENTIFY BOARD ************************************************************************** This document describes the installation of the two controller boards, WD1004- 27X and WD1004A-27X. These controllers are similar functionally, except for a few features. These boards are described below. WD1004-27X Board Figure 1-1 shows the connector locations (J1, J2, J3, J4, and J5) on the WD1004- 27X board and the location of the jumpers (W17 to W22, R23, and W25 to W28). The WD1004-27X board has a connector at J4, which allows the controller to connect power to FileCard drives and jumpers W17 to W22, which permit selection of additional options. Also the WD1004-27X board can be used as a secondary controller. WD1004A-27X Board Figure 1-2 shows the connector locations (J1, J2, J3, and J5) on the WD1004A- 27X board and the location of the jumpers (R23, and W25 to W28). The WD1004A- 27X board cannot be used as a secondary controller. Figure 1-1. WD1004-27X Connector and Jumper Locations ÚÄÄÄÄÄÄÄÄ¿ ³ ÚÄÄÙ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄij o ³ ³ o ÚÄÄJ2ÄÄÄÄ¿ ÚÄÄÄÄÄÄJ1ÄÄÄÄÄÄÄ¿ ÀÄÄÄÄij ³ ÚÄJ5ÄÄ¿ ÀÄÄÄÄÄÄÄÄÙ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ÚÄÄÄÄÄÄÄ¿ ³ ³ ÀÄÄÄÄÄÙ ÚÄÄJ3ÄÄÄÄ¿ ³ W17 ³ ³ ³ ÀÄÄÄÄÄÄÄÄÙ ÚÄÄÄÄÄÄÄÄ¿ÚÄÄÄÄÄÄÄ¿ ³ W18 ³ ³ ³ ÚÄÄ¿ÚÄÄ¿ ÚÄÄÄ¿ ³ ³³ ³ ³ W19 ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ W20 ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ W21 ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ W22 ³ ³ ³ ÀÄÄÙÀÄÄÙ ÀÄÄÄÙ ³ ³³ ³ ÀÄÄÄÄÄÄÄÙ ³ ³ ÚÄÄÄÄÄ¿ ³ ³³ ³ R23 ³ ³ ³ ³ ÀÄÄÄÄÄÄÄÄÙÀÄÄÄÄÄÄÄÙ R24 ³ ³ ³ ³ ÚÄÄÄÄÄÄÄÄÄÄÄ¿ ³ ³ ³ ³ ³ ³ ÚÄÄÄÄÄÄÄ¿ ³ ³ ³ ³ ³ ³ ³ W25 ³ ³ ³ ÀÄÄÄÄÄÙ ³ ³ ³ W26 ³ ³ ³ ÀÄÄÄÄÄÄÄÄÄÄÄÙ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ³ W27 ³ ³ ³ ³External ROM ³ ³ W28 ³ ³ ³ ³Socket ³ ÀÄÄÄÄÄÄÄÙ ³ ³ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ³ ³ ÚJ4¿ ÚÄÄÄÄÄÄÄÄÄ¿ ³ ³ o ÀÄÄÙ ÀÄÄÄÄÄÄÄÄÄÙ o ³ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ÀÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÙ Figure 1-2. WD1004A-27X Connector and Jumper Locations ÚÄÄÄÄÄÄÄÄ¿ ³ ÚÄÄÙ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄij o ³ ³ o ÚÄÄJ2ÄÄÄÄ¿ ÚÄÄÄÄÄÄJ1ÄÄÄÄÄÄÄ¿ ÀÄÄÄÄij ³ ÚÄJ5ÄÄ¿ ÀÄÄÄÄÄÄÄÄÙ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ³ ³ ÀÄÄÄÄÄÙ ÚÄÄJ3ÄÄÄÄ¿ ³ ³ ÀÄÄÄÄÄÄÄÄÙ ÚÄÄÄÄÄÄÄÄ¿ÚÄÄÄÄÄÄÄ¿ ³ ³ ÚÄÄ¿ÚÄÄ¿ ÚÄÄÄ¿ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ ³ ³ ³³ ³ ³ ³ ÀÄÄÙÀÄÄÙ ÀÄÄÄÙ ³ ³³ ³ ³ ³ ÚÄÄÄÄÄ¿ ³ ³³ ³ R23 ³ ³ ³ ³ ÀÄÄÄÄÄÄÄÄÙÀÄÄÄÄÄÄÄÙ R24 ³ ³ ³ ³ ÚÄÄÄÄÄÄÄÄÄÄÄ¿ ³ ³ ³ ³ ³ ³ ÚÄÄÄÄÄÄÄ¿ ³ ³ ³ ³ ³ ³ ³ W25 ³ ³ ³ ÀÄÄÄÄÄÙ ³ ³ ³ W26 ³ ³ ³ ÀÄÄÄÄÄÄÄÄÄÄÄÙ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ³ W27 ³ ³ ³ ³External ROM ³ ³ W28 ³ ³ ³ ³Socket ³ ÀÄÄÄÄÄÄÄÙ ³ ³ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ³ ³ ÚÄÄÄÄÄÄÄÄÄ¿ ³ ³ o ÀÄÄÄÄÄÄÄÄÄÙ o ³ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ÀÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÙ BIOS ROM Incompatibility BIOS is an acronym for Basic Input Output System. ROM is an acronym for Read Only Memory. The BIOS ROM is a program on a computer chip that tells your computer how to operate devices attached to your computer. Some XT compatible computers do not operate with the Western Digital BIOS ROM because of an incompatibility. Most of these computers are listed in Appendix A. Check Table A-1 to see if you have one of these computers. If this is the case, you need to disable the Western Digital BIOS ROM by setting a jumper resistor. If you have one of these computers, omit the low level format in this guide and instead follow your computer manufacturer's software installation instructions for low level formatting. ************************************************************************** JUMPERS ************************************************************************** A jumper allows you to change certain functions on your controller board. Western Digital set the jumpers for the most common applications. It is unlikely that you will need to change any of the jumper settings. Appendix B contains a complete explanation of jumpers. CAUTION Handle the controller board by the ends of the board. Some of the chips are static sensitive and damage may occur if the board is incorrectly handled. Do I Need To Change Any Jumpers? No. Do NOT change any jumpers on your new WD1004 or WD1004A controller boards, unless you have one of the following conditions: - The new board is your second hard disk controller in the system. - You have another peripheral unit which uses interrupt signal IRQ5. - You have a BIOS ROM which is incompatible with your new controller. - You have a hard disk drive whose parameters are different from those listed in Table 1-1. This requires you to do the dynamic configuration. Change Jumpers When you have one of the special conditions listed above, you need to add a jumper. In all other cases, do NOT add a jumper. - If the WD1004-27X board is the second controller, change the controller address at W21 & W22. Check the first controller manufacturer's manual for the addresses and also see Appendix B. - If another peripheral uses IRQ5, add a jumper at W27. - If the computer motherboard BIOS ROM is incompatible, add a jumper resistor at R23. - If you plan to do a dynamic configuration, remove the jumper at W25 and place it at W26. See Appendix B for information on changing jumpers. ************************************************************************** SET HARD DISK DRIVE CONFIGURATION ************************************************************************** This section "Set Hard Disk Drive Configuration" refers to procedures that you do to your hard disk drives and not to your WD1004 or WD1004A controller. Since the WD1004 and WD1004A boards work with many hard disk drives, you need to consult your drive manufacturer's manual for exact details. You need to set the configuration for your hard disk drive unit, before you install the unit into your computer. You set your hard disk configuration by adjusting jumpers, switches, or termination resistors on the hard disk unit. Drive Settings The two settings that you can change are: - drive number - drive termination resistor You frequently don't have to modify the factory settings. The exact number of settings that you change depends on your disk drive and computer. Control Cables (34-pin Connectors) Setting the drive number depends on the type of control cable that connects your drive to your controller board. The two types of cables are listed below. - without a twisted section - with a twisted section Do NOT use cables from floppy drives. Hard disk cables are different! First identify which cable you are going to use. Look at the control cable and determine whether it is twisted. The control cable has the 34-pin connectors. If you already have one hard disk attached to your WD1004 or WD1004A board and you plan to use the existing cable in your computer, you may have to open the computer case. See your computer manufacturer's instructions. Set Drive Number When the 34-pin control cable has a twisted section, set the jumpers or switches on both drives for drive select 2. See Figure 1-3. Ú¿ Ú¿ Ú¿ Ú¿ Ú¿ Ú¿ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄXXij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄÄÄij³ ³³ÄÄÄÄÄÄÄÄÄÄÄÄÄÄij³ÄXXij³ ÀÙ ÀÙ ÀÙ ÀÙ ÀÙ ÀÙ Non-twist Cable Twisted Cable Figire 1-3. Cables with and without a twisted section When the 34-pin control cable has NO twisted section, set a jumper or switch on the first drive for drive select 1 and the second drive for drive select 2. See the drive manufacturer's manual for detailed instructions on how to set the drive number. Set Drive Termination Resistor The drive termination resistor should only be on the drive, which is the last physical drive installed in a daisy chain configuration. When you have two hard disk drives, remove or disable the termination resistor from the drive, which you plan to attach to the middle connector . If you have only one fixed hard disk drive, do NOT change the termination resistor. Drives are usually set at the factory as the first hard disk drive (i.e., to be the only drive in the system). See the drive manufacturer's manual for detailed instructions on how to remove or disable the termination resistor. Note: A daisy chain cable has three connectors. The electrical signal in a daisy chain configuration moves from one connector to the next in sequence. ************************************************************************** CHECK COMPUTER (Incompatible System BIOS ROM) ************************************************************************** Some early versions of XT type computers have system BIOS ROMs that are incompatible with your WD1004-27X or WD1004A-27X controller. Follow the instructions in the next section "Read System BIOS ROM Date" to determine if you have one of these systems. Read System BIOS ROM Date DEBUG is a program which allows you to look at information in your computer on a fundamental level. You can enter the Debug program and use it to read a portion of your computer's ROM (read only memory). By following the steps below, you can determine the date the system BIOS ROM was created for your computer. The Debug program should be supplied on your DOS diskette. See your DOS system manual for complete instructions on how to use the Debug program. Place the diskette containing the Debug program in drive A, then 1. At the prompt (A>), Type: DEBUG Press 2. At the debug prompt (-), Type: d f000:fff5 fffc Press 3. Date returned is (10/27/82) OR LATER 4. To exit debug, Type: q Press 2 HOW TO INSTALL YOUR HARDWARE This section tells you how to install the hardware portion of your WD1004-27X or WD1004A-27X controller board. You will install the controller board in an XT- compatible expansion slot. Do not attempt to install your hardware unless you have set the hard disk drive configuration as explained on page 1-9 and set the WD1004 or WD1004A board jumpers, if required. The installation requires you to remove the cover from your computer. See your PC manual for exact instructions on how to remove the cover. @BODY TEXT PBA = If you are replacing an existing controller, then you also have to remove your old hard disk controller. If you want two hard disks on one controller, use a daisy chain cable to connect them onto one controller board. A daisy chain cable has 3 connectors. 1. Turn your computer power switch to OFF and unplug power cord. 2. Use a screwdriver to loosen the cover screws. Then remove the computer cover, so that you can see the expansion slots. 3. Place your hard disk drive unit(s) into the computer case and mount per the manufacturer's installation instructions. 4. Look and see which expansion slots are empty. Use an empty slot that has the same type of edge connectors as the WD1004 or WD1004A board, except as noted below. Note: For IBM XT owners: DO NOT use the slot closest to the power supply. Use an expansion slot at least one position removed from the power supply. You may have to leave the fastening screws loosely connected, so that you can attach the cables. Or if you are removing a controller, locate the one which has the old controller in it. Use this expansion slot. Note: You can also install a new fixed hard disk drive on an existing WD1004 or 1004A controller. See Appendix A. 5A. If you are removing an old controller, loosen the screw which holds the old controller board in place. Then slide the old board out of the expansion slot and remove the cables. Locate the old rear slot cover and place it on your computer case. (You probably removed this old slot cover when you installed your old controller board.) 5B. If you are using a "new" expansion slot, remove the screw, but keep the rear slot cover in place. Save the screw to hold the new controller board. 6. Connect 34-pin wide control cable to your WD1004 or WD1004A board. Follow steps A or B. These instructions are for both one or two drives on the same controller. A. (for 1 drive only) Connect the 34-pin (wide control cable) connector to J1 on the controller board. Attach Pin 1 of the cable connector to Pin 1 on the controller board. See Figure 1-1 or Figure 1-2. Pin 1 of the cable connector is marked and is on the color coded edge of the cable. Do NOT force the cables and connectors. B. (for 2 drives only) If you are installing two hard disk drives on one controller, use a daisy chain cable. A daisy chain cable has 3 connectors. Connect the 34-pin wide connector on the longer daisy chain cable section to J1 on the WD1004 or WD1004A board. See Figure 1-1 or Figure 1-2 and Figure 2-1. 7. Connect 34-pin wide control cable to drive unit. ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ³ FIRST DRIVE ³ÄÄÄ¿ 34 Pin Connector ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙÄÄ¿³ ³³ ³³ (Shortest Cable) ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ³³ ³ SECOND DRIVE ³ÄÄÙ³ 34 Pin Connector ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙÄÄ¿³ (Termination Resistor ³³ Removed) ³³ (Longest Cable) ³³ ³³ ³³ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÙ³ ³ ÚÄÄÄÄÄÄÄÄÄÄÄÄÙ ÚÄÄÄÄÄÄÄijijÄÄÄ¿ 34 Pin Connector ³ J1 ³ ÀÄÄ¿ ÚÄÄÙ ÀÁÁÁÁÁÁÁÁÙ WD1004-27X or WD1005A-27X Figure 2-1. Daisy Chain Cable Connections A. (for 1 drive only) Connect the free end of the 34-pin control cable to the hard disk drive. B. (for 2 drives only) Connect the end 34-pin connector on the shorter daisy chain cable section to the first hard disk drive unit's 34-pin connector. See Figure 2-1. C. (for 2 drives only) Connect the middle 34-pin connector on the shorter daisy chain cable section to the second hard disk drive unit's 34-pin connector. Remember: The second hard disk drive unit is the unit from which you removed or disabled the termination resistor and changed the drive number. See page 1-12. 8. Connect 20-pin data cable(s) to the drive unit(s) 20-pin connectors. Attach one 20-pin data cable to the first hard disk drive unit. If you are installing a second drive connect the second 20-pin data cable to the second hard disk drive unit. 9. Connect 20-pin data cable(s) to the WD1004 or WD1004A board as described below. A. Connect the 20-pin data cable from the first drive to J2 on the controller board. Attach Pin 1 on the cable to Pin 1 on the controller board. See Figure 1-1 or Figure 1-2. B. (for 2 drives only) If you install a second hard disk drive, connect the second 20-pin data cable from the second drive to J3 on the controller board. See Figure 1-1 or Figure 1-2. 10. (optional for systems with LED cables & J5 connectors) Connect the 4-pin external LED cable connector to J5 on the controller board. This instruction only applies to WD1004-27X controllers. 11. Connect power from your computer's internal power supply to the drive. Follow instructions for either A or B. A. Locate the internal 4-pin power connector(s) on your computer. See your computer manual. Connect this internal 4-pin power connector to your fixed hard disk drive unit's power connector plug. B. (for 2 drives only) If you are installing 2 drives, you need either two internal power connectors on your computer or you need a "y" adapter, which splits the power cable. See the manufacturer's manual. Connect the second drive unit to the second power connector plug or to the "y" adapter. 12. Install the controller board into the expansion slot that you selected in step 4. The WD1004 or WD1004A's edge connectors (shown in Figure 1-1 or Figure 1-2) fit firmly into the computer's motherboard. See your computer manual for the location of your computer's motherboard. Press firmly on the WD1004 or WD1004A board as you insert it into the expansion slot. Check that the board is seated properly by pressing down firmly on both ends of the board. 13. After the board is seated firmly in the expansion slot socket, secure the board using the clip that is on the end of your board. Place the bracket screw (which you removed in step 5) over the clip and rear slot cover. Then screw the clip and slot cover to the computer chassis. CAUTION When routing cables, be careful not to pinch them. Cables must not get caught between the cover and the boards nor should they obstruct any air flow path from fans or vents. 14. Place extra cable lengths so that they are out of the way. 15. Replace the computer cover. Then plug the power cord back into your computer. Your hardware controller installation is complete. However, your WD1004 or WD1004A controller board is really a complex circuit composed of both hardware and software, so that while the hardware installation is complete, you still need to install the software. Proceed to the next section for the software installation steps. Tighten hard disk unit(s) to computer case, etc. if not already done so in step 3.