Narrow to Wide SCSI Upgrade Instructions
FIRST EDITION: January 1998 To re-order this document, request part number PDI-00440-70 FCC Notice This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment.
Table of Contents INTRODUCTION.....................................................................................................................................1 About the Wide SCSI Bus.....................................................................................................................1 COMPATIBILITY....................................................................................................................................1 ELECTRONIC EQUIPMENT HANDLING PRECAUTIONS.................
INTRODUCTION This document describes the installation procedures for a 68-pin Wide SCSI bus cable (PDB-00440-7x) in the following four types of chassis: • Deskside • AM-990 and AM-990 double-wide (jumbo): these chassis accept either a standard Wide SCSI cable or the High-Capacity Wide SCSI Internal Cable, PDB-00440-75. This cable allows up to nine internal devices, but no external cabling.
Page 2 Narrow to Wide SCSI Upgrade Instructions For optimum performance, use only Wide SCSI-2 disk drives on the Wide SCSI bus. Mixing SCSI-1, SCSI-2, and Wide SCSI-2 disks on the same bus tends to degrade performance and is not recommended. ELECTRONIC EQUIPMENT HANDLING PRECAUTIONS With the AC power cord unplugged and the top cover removed, the components inside your computer are vulnerable to damage caused by static discharge.
Narrow to Wide SCSI Upgrade Instructions Page 3 Before you loosen the first screw, make sure all your data is copied onto some form of backup media. UPGRADE PROCEDURE Here is a brief summary of the steps you must follow to complete your upgrade: 1. Remove your computer’s covers to expose the CPU board. 2. Remove the 50-pin SCSI bus cable from the CPU board. 3. Remove the 50-pin external SCSI terminator. Disconnect all SCSI devices. 4.
Page 4 Narrow to Wide SCSI Upgrade Instructions ETHERNET PORT XBUS A/D CONN P4 JP1 DISC P1 PROGRAM DO NOT USE P3 JP2 JP11 RX CD TX XBUS C/S CONN P6 JP3 P2 - NARROW SCSI CONNECTOR T2 P5 BANK 0 BANK 1 P2 D1 D2 D3 JP4 P5 - WIDE SCSI CONNECTOR JP5 33 25 18 32 XCLK JP7 JP6 CDIS MDIS JP8 JP9 68060 CPU - + FAN JP10 ALPHA MICROSYSTEMS J1 AM-176-00 Rev C00 CACHE SIMM LOW BANK 0 J2 LOW BANK 1 J3 HIGH BANK 0 J4 HIGH BANK 1 J5 P8 +5V +12V P7 SERIAL P9 Figure 2: AM-176 Boar
Narrow to Wide SCSI Upgrade Instructions Page 5 DESKSIDE CHASSIS This section describes how to install the Wide SCSI cable kit (PDB-00440-70) in a deskside chassis. While your computer's hardware is exposed and the AC power cord is unplugged, the components are vulnerable to damage caused by static discharge. Before you handle any computer hardware, make certain your work area is properly protected against static discharge. Removing the Chassis Cover 1. Power down your computer and unplug the power cord.
Page 6 Narrow to Wide SCSI Upgrade Instructions Removing the 50-Pin SCSI Cable Observe the routing of the existing SCSI cable before you remove it—you will route the Wide SCSI cable along the same path. 1. Remove the bail mount clips for the external narrow SCSI connector from the rear panel. Do not remove any cables other than the SCSI cable. 2. Unplug the 50-pin SCSI cable from P2 on the AM-176 board. 3. Unplug the 50-pin SCSI cable from all SCSI peripherals and remove the cable.
Narrow to Wide SCSI Upgrade Instructions Page 7 AM-990 AND AM-990 JUMBO CHASSIS This section describes how to install the Wide SCSI cable kit, PDB-00440-71, in an AM-990 chassis, or upgrade kit PDB-00440-72 in an AM-990 Jumbo chassis. It also covers installing the High-Capacity Wide SCSI Internal Cable, PDB-00440-75, in either AM-990 chassis. While your computer's hardware is exposed and the AC power cord is unplugged, the components are vulnerable to damage caused by static discharge.
Page 8 Narrow to Wide SCSI Upgrade Instructions 4. To remove the side panel: • Swing the front door open to gain access to the screws that hold the side panel to the chassis. • Remove the four screws along the left edge (behind the front door). Lift the side panel, slide it to the front, and place it out of the way. • To expose the AM-176 board, remove the card cage lid (DWF-20670-00) by removing the five screws, lifting it out, and placing it out of the way.
Narrow to Wide SCSI Upgrade Instructions Page 9 The High-Capacity Wide SCSI Internal Cable, PDB-00440-75, does not have an external connector. To install it, follow these instructions: 1. Plug the 68-pin Wide SCSI bus cable into the connector at P5 on the AM-176 board. 2. Route the Wide SCSI bus cable over the top of the bracket so it cannot interfere with the fan on the AM-176 board. 3. Route the Wide SCSI cable to the SCSI peripherals. Plug the cable into each disk or tape drive.
Page 10 Narrow to Wide SCSI Upgrade Instructions PEDESTAL CHASSIS This section describes how to install the Wide SCSI cable kit (PDB-00440-73) in a pedestal chassis. While your computer's hardware is exposed and the AC power cord is unplugged, the components are vulnerable to damage caused by static discharge. Before you handle any computer hardware, make certain your work area is properly protected against static discharge. Accessing Your Hardware 1. Power down your computer and unplug the power cord.
Narrow to Wide SCSI Upgrade Instructions Page 11 If you are connecting narrow SCSI devices to a Wide SCSI cable, be sure to use the appropriate adapter between the device and the cable connector. 3. Mount the new Wide SCSI cable/adapter plate assembly onto the existing SCSI cutout using the standoffs provided with your upgrade kit. 4. Make sure the Wide SCSI cable is terminated properly. This normally means plugging an external active terminator into the external Wide SCSI port on the rear panel.
Page 12 Narrow to Wide SCSI Upgrade Instructions Removing the 50-Pin SCSI Bus Cable Observe the routing of the existing SCSI cable before you remove it—you will route the Wide SCSI cable along the same path. 1. Remove the bail mount clips for the external SCSI connector from the rear panel. 2. Unplug the 50-pin SCSI bus interface from P2 on the AM-176 board. 3. Unplug all the SCSI devices connected to the SCSI bus cable. Also remove any adapters being used to attach Wide SCSI devices to the narrow cable.
Appendix A - SCSI Termination SCSI TERMINATION USING AN EXTERNAL TERMINATOR The SCSI bus must be terminated at each end of the cable. The CPU board terminates one end of the bus. The preferred method of terminating the other end of the SCSI bus in an AMOS computer is the installation of an external terminator. In April 1993, the external SCSI bus terminator became standard on all AMOS computers.
Page A-2 Appendix A Figure 5 shows an active external Wide SCSI connector and thumbscrews for holding the terminator in place. This configuration is used on almost all of Alpha Micro's currently available product. The terminator is installed by sliding it over the connector and fastening the thumbscrews to the standoffs in the terminator. ATTACHING EXTERNAL DEVICES To attach an external SCSI device, you must remove the terminator from the external SCSI port.
