Page 1 SPARCstation 20 Service Manual Sun Microsystems Computer Company A Sun Microsystems, Inc. Business 901 San Antonio Road Palo Alto, CA 94303-4900 USA 650 960-1300 fax 650 969-9131 Part No.: 801-6189-12 Revision A, July 1996 Send comments about this document to: docfeedback@sun.com...
Page 2 FAR 52.227-19(6/87), or DFAR 252.227-7015(b)(6/95) and DFAR 227.7202-3(a). Sun, Sun Microsystems, the Sun logo, and Solaris are trademarks or registered trademarks of Sun Microsystems, Inc. in the United States and in other countries. All SPARC trademarks are used under license and are trademarks or registered trademarks of SPARC International, Inc. in the United States and in other countries.
Page 3: Table Of Contents
Contents Product Description 1 Standard Features 1 Subassemblies, Boards, and Components 2 Interior View 3 Rear View 4 Software Requirements 6 Internal Options 6 External Options 7 Troubleshooting Overview 9 Default Boot Mode 9 Diagnostic Tools 11 OpenBoot PROM Diagnostics 12 SunDiag System Exerciser 14 Sun VTS 15 Power-On Self Test (POST) 17...
Page 4 Electrostatic Discharge (ESD) Precautions 42 Power On and Off 45 Removing Power from the System 45 Restarting the System While Troubleshooting 46 Reading Boot Messages 47 Turning On the Power 47 Internal Access 49 SPARCstation 20 Service Manual • July 1996...
Page 5 Removing the Cover 49 Attaching the Wrist Strap 50 Replacing the Cover 51 Removing and Installing Subassemblies 55 Power Supply 55 Removing the Power Supply 55 Installing the Power Supply 58 LED 60 Removing the LED 60 Installing the LED 63 Speaker 64 Removing the Speaker 64 Installing the Speaker 66...
Page 6 Diskette Drive 126 Removing a Diskette Drive 127 Installing a Diskette Drive 132 System Board Overview 139 Preventing Damage 139 Handling System Boards and Assemblies 139 System Board Description 140 System Board FRUs 141 SPARCstation 20 Service Manual • July 1996...
Page 7 System Board and Component Replacement 143 MBus Module 143 Removing a Single-Wide MBus Module 143 Installing a Single-Wide MBus Module 146 Removing a Double-Wide MBus Module 147 Installing a Double-Wide MBus Module 149 SBus Card 152 Removing an SBus Card 152 Installing an SBus Card 156 DSIMMs, VSIMMs, and NVSIMMs 159 DSIMM 159...
Page 8 Clock Chip 204 System Board Connector Pinouts 205 Parallel Connector 205 AUI Connector 207 Keyboard and Mouse Connector 209 Serial Ports A and B Connector 210 Twisted-Pair Ethernet Connector 211 SCSI Connector 212 viii SPARCstation 20 Service Manual • July 1996...
Page 9 13W3 Connector 215 Audio Ports 216 Headphone Connector 217 SCSI Addresses 219 Disk Drives 219 Selected On-Board Diagnostics 221 test device alias, test device pathname 221 test-all 222 watch-clock 223 watch-net, watch-aui, watch-tpe, watch-net-all 224 probe-scsi, probe-scsi-all 226 test-memory 227 power-off 228 module-info 228 Glossary 229...
Page 10 SPARCstation 20 Service Manual • July 1996...
Page 11 SPARCstation 20 System 2 FIGURE 1-1 SPARCstation 20 System Exploded View 3 FIGURE 1-2 SPARCstation 20 System Overhead Interior View 4 FIGURE 1-3 SPARCstation 20 System Unit Rear View 5 FIGURE 1-4 Default Boot Mode (OpenBoot PROM Version 2.14 or Later) 10...
Page 12 Routing Excess Cables in Cable Trough 82 FIGURE 8-24 Fan DC Power Connector 83 FIGURE 8-25 SCSI Backplane Sockets and Connectors 85 FIGURE 8-26 SCSI Backplane Screws 86 FIGURE 8-27 SCSI Backplane Bracket Tabs 87 FIGURE 8-28 SPARCstation 20 Service Manual • July 1996...
Page 13 Internal Cables and DC Power Connector (SunCD 2Plus Drive-Type Chassis) 89 FIGURE 8-29 Back Panel SBus Slots and Captive Screws 90 FIGURE 8-30 SCSI Backplane, SCSI Data, and DC Power Connectors 90 FIGURE 8-31 Cable Guide Detail 92 FIGURE 8-32 Internal Cables and DC Power Connector (SunCD 4 Drive-Type Chassis) 94 FIGURE 8-33 Removing the System Board 95...
Page 14 FIGURE 11-10 SBus Card Retainers 153 FIGURE 11-11 SBus Card Back Plate Screws and Washers 153 FIGURE 11-12 Installing the Card Extractor 154 FIGURE 11-13 Removing a Double-Wide SBus Card 154 FIGURE 11-14 SPARCstation 20 Service Manual • July 1996...
Page 15 Removing the SBus Card Extractor 155 FIGURE 11-15 Removing the SBus Card Adapter Bracket 156 FIGURE 11-16 Installing a Double-Wide SBus Card 157 FIGURE 11-17 Installing a Single-Wide SBus Card 157 FIGURE 11-18 SBus Card Back Panel Screws and Washers 158 FIGURE 11-19 DSIMM, Front View 159 FIGURE 11-20...
Page 16 FIGURE C-7 Back Panel Audio Ports and Icons 216 FIGURE C-8 Microphone Icon 217 FIGURE C-9 Audio Line-Out Icon 217 FIGURE C-10 Audio Line-In Icon 217 FIGURE C-11 Audio Line-in Icon 217 FIGURE C-12 SPARCstation 20 Service Manual • July 1996...
Page 17 Tables SPARCstation 20 System Configurations and Software Requirements 6 TABLE 1-1 Internal Options 6 TABLE 1-2 External SCSI Options 7 TABLE 1-3 Diagnostic Tools 11 TABLE 2-1 Autoboot and Diagnostic Switch Settings 12 TABLE 2-2 OpenBoot PROM Diagnostic Tests 12...
Page 18 Audio Port Signals 216 TABLE C-8 SCSI Addresses, Solaris 1.1.1 Version B (SunOS 4.1.3_U1 Version B) Operating TABLE D-1 Environment 219 SCSI Addresses, Solaris 2.3 (SunOS 5.3) Operating Environment and Later Versions 220 TABLE D-2 xviii SPARCstation 20 Service Manual • July 1996...
Page 19 Part 1, “System Chapter 1, “Product Describes the standard features, internal Information” Description” options, and external options of the SPARCstation 20 system Part 2, “Troubleshooting” Chapter 2, “Troubleshooting Describes how to diagnose a problem and Overview” run diagnostic tests Chapter 3, “Power-On Self-Test Describes the execution of POST and (POST)”...
Page 20 Explains how to work safely when servicing Service” Requirements” the SPARCstation 20 system Chapter 6, “Power On and Off” Provides step-by-step procedures to power on and power off the SPARCstation 20 system Part 4, “Subassembly Chapter 7, “Internal Access” Provides step-by-step procedures to remove Removal and the SPARCstation 20 system cover, attach the Replacement”...
Page 21 Procedures in this document must be performed by trained maintenance providers. Only people who have been trained by the Sun MicrosystemsTM™ training facilities (or by Sun Microsystems affiliates) and have been certified as required by local and national laws are considered qualified.
Page 22 Read Chapter 6 in User’s Guide. These be emphasized are called class options. You must be root to do this. Related Documentation The following table lists related documentation supporting SPARCstation 20 operation: Related Documentation TABLE P-3 Document Title Part number OpenBoot™...
Page 23 TABLE P-3 Document Title Part number SunVTS™™ 2.0 Quick Reference Card 802-5329 Product Notes—SPARCstation 20 801-7464 System administration manual for your computer system Operating system documentation UNIX Commands This manual does not include specific software commands or procedures. Instead, it names software tasks and refers to operating system documentation or the handbook that was shipped with the hardware.
Page 24 Bourne shell, and Korn shell. Shell Prompts TABLE P-4 Shell Prompt C shell prompt machine_name% C shell superuser prompt machine_name# Bourne shell and Korn shell prompt Bourne shell and Korn shell superuser prompt xxiv SPARCstation 20 Service Manual • July 1996...
Page 25: Product Description
(VSIMMs). Installing a second VSIMM is done through the optional auxiliary video board (AVB). Standard Features The SPARCstation 20 system has four audio ports on the back panel and contains an internal speaker. A variety of internal storage devices are available: 535-Mbyte hard disk drive 1.05-Gbyte hard disk drive...
Page 26: Subassemblies, Boards, And Components
SPARCstation 20 System FIGURE 1-1 Subassemblies, Boards, and Components The SPARCstation 20 system contains the following subassemblies, boards, and components (see FIGURE 1-2 System board SIMMs DSIMMs (eight maximum) VSIMMs (two maximum) Non-volatile SIMM (NVSIMM) (one) SBus card (four maximum) MBus module (two maximum) Hard disk drive, 3.5-inch (88.0-mm), single connector (two maximum)
Page 27: Interior View
Fan DC power cable Diskette filler Power panel supply Chassis External power cord SPARCstation 20 System Exploded View FIGURE 1-2 Interior View shows an interior view of the major subassemblies and the system board. FIGURE 1-3 Chapter 1 Product Description...
Page 28: Rear View
Appendix C provides additional FIGURE 1-4 information. The appendix describes each connector on the back panel, lists pin assignments, signal descriptions, and shows detailed connector illustrations. SPARCstation 20 Service Manual • July 1996...
Page 29: Figure 1-4 Sparcstation 20 System Unit Rear View
8—SCSI 3—Lock block 9—Twisted-pair Ethernet 4—MBus 10A—Parallel 5—SBus 10B—AUI Ethernet 6—AVB (13W3 video) 11—Keyboard 7A—Audio, headphone 12—Serial port A/B 7B—Audio, microphone 13—13W3 video 7C—Audio, line-out 14—AC power receptacle SPARCstation 20 System Unit Rear View FIGURE 1-4 Chapter 1 Product Description...
Page 30: Software Requirements
Systems Solaris 2.3 (SunOS 5.3) software environment with Solaris 2.3 configured with Supplement, Revision B, or later Solaris 2.x releases VSIMMs Internal Options lists the internal options of the SPARCstation 20 system. TABLE 1-2 Internal Options TABLE 1-2 Quantity Option (max.)
Page 31: External Options
Internal Options (Continued) TABLE 1-2 Quantity Option (max.) Description Diskette drive Internal diskette drive; triple density MS-DOS/ IBM compatible Operates with the second VSIMM option; provides second 13W3 video output DSIMM Supports up to 512 Mbytes of DSIMMs; DSIMM capacities are: 16-, 32-, and 64-Mbyte VSIMM Supports up to 2 VSIMMs;...
Page 32 Requires a minimum of two SCSI controllers if all three trays are used. No more than seven SCSI devices on each SCSI bus. Multiple disk pack Desktop enclosure containing a disk array of SCSI disk drives SPARCstation 20 Service Manual • July 1996...
Page 33: Troubleshooting Overview
C H A P T E R Troubleshooting Overview This chapter describes how to diagnose a problem and execute diagnostic tests. Default Boot Mode is a flow diagram of the default boot mode for OpenBoot PROM Version FIGURE 2-1 2.14 or later. The default boot mode initiates the power-on self-test (POST) diagnostics if any one of the following conditions exists: Keyboard Stop (L1) and D keys are pressed and held down diag-switch? parameter is set to true...
Page 34 “disk” passed? interpret their drivers. Boot user speciﬁed device Display errors on keyboard and program to A LEDs and serial port A Default Boot Mode (OpenBoot PROM Version 2.14 or Later) FIGURE 2-1 SPARCstation 20 Service Manual • July 1996...
Page 35: Diagnostic Tools
Diagnostic Tools Diagnostic tools include power-on self-test (POST), OpenBoot PROM diagnostics, SunDiag system exerciser, and Sun verification test suite (SunVTS). A description of the POST is provided in Chapter 3. lists the diagnostic tools and provides a TABLE 2-1 description of each. lists switch settings and results for the autoboot switch TABLE 2-2 and the diagnostic switch.
Page 36: Openboot Prom Diagnostics
Performs an internal and external A cable must be connected between the system test net loopback test on the auto-selected and the Ethernet transceiver or hub. system Ethernet interface SPARCstation 20 Service Manual • July 1996...
Page 37 OpenBoot PROM Diagnostic Tests (Continued) TABLE 2-3 Type of Test Description Preparation test disk Tests internal or external SCSI disks The disk drive must be spinning before this test disk0 that have self-test diagnostic programs test is executed; enter a boot disk alias test disk1 on the drive controller command to cause the drive to spin up.
Page 38: Sundiag System Exerciser
Note – If a SunDiag system exerciser error message is not descriptive enough, execute the POST for a more descriptive explanation (see Chapter 3.) SPARCstation 20 Service Manual • July 1996...
Page 39: Sun Vts
Sun VTS The SunVTS software executes multiple diagnostic hardware tests from a single user interface and is used to verifying configuration and functionality of most hardware controllers and devices. SunVTS operates primarily from the OpenWindows™™ user interface, allowing test parameters to be set quickly and easily while a diagnostic test operation is being performed.
Page 40 The SunVTS teletype (vtstty) diagnostic tool controls the vtsk from either a command shell or a terminal attached to a serial port. Most options available in vtstty have equivalent options in vtsui. vtstty is applicable to server configurations only. SPARCstation 20 Service Manual • July 1996...
Page 41: Power-On Self Test (Post)
C H A P T E R Power-On Self Test (POST) The Power-on self-test (POST) diagnostics reside in the OpenBoot PROM, which is located on the system board. There are three POST modes: normal, full diagnostic, and abbreviated diagnostic. The following is a list of the POST diagnostic topics presented in this chapter.
Page 42 If a terminal is not connected to serial port A, or a tip connection is not implemented, the screen will be blank during the POST diagnostic test mode. In this case, the keyboard LEDs are used to determine error conditions. See “Status LEDs and Indicators.” SPARCstation 20 Service Manual • July 1996...
Page 43: Abbreviated Diagnostic Mode
SunOS™™ to help in working with the OpenBoot PROM. To set up a tip connection, proceed as follows: 1. Connect the SPARCstation 20 serial port A to another Sun Workstation serial port using a serial connection cable. This connection is made with a 3-wire null modem cable.
Page 44: Post Tests
The shell window is now a tip window directed to the Sun Workstation serial port. When powering on the SPARCstation 20 in diagnostic mode, messages will be displayed at this window. 4. When POST is completed, disconnect the tip window by typing ~.
Page 45 Sample Listing of the Full Diagnostic Mode Test CODE EXAMPLE 3-3 SMCC SPARCstation 10/20 UP/MP POST version xxx (xx/xx/xxxx) CPU_#0 TI, TMS390Z55(3.x) 1Mb External cache CPU_#2 TI, TMS390Z55(3.x) 1Mb External cache CPU_#1 ******* NOT installed ******* CPU_#3 ******* NOT installed ******* <<<...
Page 46 DMA2/MACIO D_NADDR Reg. Test ESP Registers Tests DMA2/MACIO P_CSR Reg. Test DMA2/MACIO P_ADDR Reg. Test DMA2/MACIO P_BCNT Reg. Test PPORT Registers Tests DMA2/MACIO PPORT IO Lpbck Tst DMA2/MACIO PPORT XFR Lpbck Tst TOD Registers Test SPARCstation 20 Service Manual • July 1996...
Page 47: Post Error Messages
POST Error Messages Most POST error messages are displayed at the system monitor and are self- explanatory. Use the error messages returned by POST to troubleshoot the system. lists typical POST error messages. CODE EXAMPLE 3-4 Typical POST Error Messages CODE EXAMPLE 3-4 STATUS : Power-On SelfTest FAILED ...
Page 48: Figure 3-1 System Led Location
Note – During normal system operation, the keyboard key LEDs should not be interpreted as diagnostic error indicators. Note – The Caps Lock key LED is not used as a power-on test failure indicator, but flashes on and off while POST is initialized. SPARCstation 20 Service Manual • July 1996...
Page 49: Completing Post
Scroll Lock Num Lock key indicator key indicator Compose key indicator Caps Lock key indicator Type-5 Keyboard Key LEDs FIGURE 3-2 Keyboard Key LED Description TABLE 3-1 LED State Description Caps Lock flashing or lit POST is executing Num Lock on System board failure Scroll Lock on MBus module in slot 0 failure...
Page 50 SPARCstation 20 Service Manual • July 1996...
Page 51: Troubleshooting Procedures
C H A P T E R Troubleshooting Procedures This chapter describes how to troubleshoot possible problems and includes suggested corrective actions. identifies system problems and corrective TABLE 4-1 actions. Troubleshooting Tips TABLE 4-1 System Problem Corrective Action LED on front of system not lit Verify that the power switch is turned on and that the power cord is connected to the system and an AC receptacle.
Page 52: Video Output Failure
VSIMM. VSIMMs can be installed in one or two of the memory slots: Slot J0304 is the default slot for the VSIMM in SPARCstation 20 systems with the SX graphics option. This enables video output on the monitor connector on the system back panel.
Page 53: Power-On Does Not Succeed
5. If the monitor power supply is internally fused, check the fuse. Power-On Does Not Succeed To check for a power-on failure: 1. Remove the DC power from the system by pushing the back panel power switch to the standby position. 2.
Page 54: Figure 4-1 Power Supply Connector Pinouts
2. Replace the power supply assembly if any of the voltages are not present. See “Power Supply” on page 55. 1 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 Power Supply Connector Pinouts FIGURE 4-1 SPARCstation 20 Service Manual • July 1996...
Page 55: System Board Test
Power supply connector Power supply Power-on/standby switch External power cord Power Supply and Power Supply Connector Location FIGURE 4-2 Power Supply Connector Pin Assignments TABLE 4-2 Color Description Color Description Blue Black Ground Brown Black Ground Black Ground Black Ground Black Ground Black...
Page 56: Caps Lock Key Fails To Flash During The Post
5. If POST passes with the optional parts removed, install the optional parts one at a time. Initiate POST after each optional part is installed; observe the diagnostic output on serial port A and the keyboard LEDs. SPARCstation 20 Service Manual • July 1996...
Page 57: Disk Drive Errors
Disk Drive Errors The following procedure verifies the built-in SCSI controller. lists disk TABLE 4-3 drive error conditions and corrective actions. To test the disk drive: Note – To verify if the built-in SCSI controller is defective, test the disk drive response to the probe-scsi command.
Page 58: Table 4-3 Troubleshooting Disk Drive Errors
1.05-Gbyte disk drive, install an FSBE/S SCSI host adapter card to the “fast SCSI” devices and put these “fast SCSI” devices on a separate SCSI bus to accelerate disk drive response. SPARCstation 20 Service Manual • July 1996...
Page 59: Simm Errors
SIMM Errors If the operating system, diagnostic program, or POST does not display a SIMM location (“J” number) as part of the memory error message and the only available information is a physical memory address, use to locate the failing SIMM. TABLE 4-4 SIMM Slots and Physical Address TABLE 4-4...
Page 60: Figure 4-3 System Board Simm Slot Locations
VSIMMs and/or NVSIMM Installation Sequence Slot Layout DSIMM J0201 DSIMM0 DSIMM J0202 DSIMM1 DSIMM J0203 DSIMM2 DSIMM J0301 DSIMM3 DSIMM J0302 DSIMM4 DSIMM J0303 DSIMM5 J0407(VSIMM0) J0304(default) (DSIMM6) J0406(VSIMM1 or NVSIMM) J0305 (DSIMM7) SPARCstation 20 Service Manual • July 1996...
Page 61 Note – A DSIMM must be installed in J0201 for the system to function properly. Chapter 4 Troubleshooting Procedures...
Page 62 SPARCstation 20 Service Manual • July 1996...
Page 63: Safety And Tools Requirements
C H A P T E R Safety and Tools Requirements This chapter provides a description of safety requirements, symbols, safety precautions, and required tools. Safety Requirements For your protection, observe the following safety requirements: Follow all cautions, warnings, and instructions marked on the equipment. Ensure that the voltage and frequency rating of the power outlet to be used matches the electrical rating labels on the system.
Page 64: Symbols
Do not touch the metal heat sinks on the MBus module MBus module, and or the system board. The heat sinks can be hot enough to system board cause personal injury. Symbols The following symbols are used throughout this manual: SPARCstation 20 Service Manual • July 1996...
Page 65: System Precautions
Procedures contained in this document must be performed by trained maintenance providers. Only people who have been trained by the Sun Microsystems training facilities (or by Sun Microsystems affiliates) and have been certified as required by local and national laws are considered qualified.
Page 66: Lithium Battery
Lithium Battery Caution – On SPARCstation 20 system boards, there is a lithium battery molded into the real-time clock, SGS No. MK48T18. Batteries are not customer replaceable parts. They may explode if mistreated. Do not dispose of the battery in fire. Do not disassemble it or attempt to recharge it.
Page 67 When removing a board, card, or module from an antistatic bag, lay it on an antistatic surface such as a Sun ESD mat, an antistatic bag, or a disposable antistatic mat. Transport boards, cards, or modules in an antistatic bag. Always wear an antistatic wrist strap connected to a metal surface on the chassis when working on system components and parts.
Page 68 SPARCstation 20 Service Manual • July 1996...
Page 69: Power On And Off
C H A P T E R Power On and Off Removing Power from the System To remove power from the system: Caution – Failure to terminate the operating system can cause data loss. Note – Before turning off the system power, terminate the operating system. 1.
Page 70: Restarting The System While Troubleshooting
2. Turn the power on as follows: a. SCSI peripheral farthest from the system (peripheral with the SCSI terminator attached) b. SCSI peripheral closest to the system (peripheral directly connected to the system) SPARCstation 20 Service Manual • July 1996...
Page 71: Reading Boot Messages
After POST completes the system self-test, a message similar to the following is displayed, listing hardware detected in the system. SPARCstation 20 Series (2 X XXXXXX) ROM Rev. -.-, --- MB Memory installed, Serial #---. Ethernet address -:-:--:-:--:--, Host ID: ------.
Page 72: Figure 6-2 Power-On Switch
Power on/Standby switch on the system back panel ( FIGURE 6-2 2. The operating system should load or the ok prompt should appear on the monitor. Power on Power-On Switch FIGURE 6-2 SPARCstation 20 Service Manual • July 1996...
Page 73: Internal Access
C H A P T E R Internal Access This chapter explains how to remove the cover, attach the wrist strap, and replace the cover. Removing the Cover To remove the cover: 1. Remove power from the system. See “Removing Power from the System” on page 45 2.
Page 74: Attaching The Wrist Strap
1. Unwrap the first two folds of the wrist strap. Wrap the adhesive side firmly around the wrist ( FIGURE 7-3 2. At the opposite end of the wrist strap, peel the liner from the copper foil. Attach the copper foil to the power supply metal casing. SPARCstation 20 Service Manual • July 1996...
Page 75: Replacing The Cover
Wrist strap Power supply Grounding Wrist Strap to Power Supply FIGURE 7-3 Replacing the Cover To replace the cover: 1. Remove the wrist strap. 2. Grasp the cover by the front and rear edges ( FIGURE 7-4 Chapter 7 Internal Access...
Page 76: Figure 7-4 Replacing The Cover
Ensure that the tabs are locked into the chassis slots. 4. Lower the cover onto the chassis ( FIGURE 7-4 5. Replace the lock block ( FIGURE 7-5 Lock Block FIGURE 7-5 SPARCstation 20 Service Manual • July 1996...
Page 77: Figure 7-6 Back Panel Corner Screw
Caution – Do not use a power driver to tighten the back panel screws. Do not overtighten the back panel screws. 6. Tighten the screw on the back panel corner and secure the cover ( FIGURE 7-6 Corner screw Back Panel Corner Screw FIGURE 7-6 Chapter 7 Internal Access...
Page 78 SPARCstation 20 Service Manual • July 1996...
Page 79: Removing And Installing Subassemblies
C H A P T E R Removing and Installing Subassemblies This chapter contains procedures for removing and installing the major subassemblies of the system unit. The following is the list of the major subassemblies: Power Supply To remove and install the power supply, proceed as follows. Removing the Power Supply Caution –...
Page 80 Disconnect the DC power connector from the system board. c. Slide the power supply toward the drive bracket and free of the chassis mounts. d. Lift the power supply from the chassis. SPARCstation 20 Service Manual • July 1996...
Page 81: Figure 8-1 Attaching A Wrist Strap To Back Panel And Removing The Power Supply
Power supply Power rear view supply DC power harness DC power connector Drive bracket Captive screw (2) System unit backplane metal edge Wriststrap Attaching a Wrist Strap to Back Panel and Removing the Power Supply FIGURE 8-1 5. Disconnect the DC power harness from the rear of the power supply ( FIGURE 8-2 6.
Page 82: Installing The Power Supply
4. Tighten the captive screw(s) that secure the power supply to the chassis FIGURE 8-3 Note – Some systems use only one captive screw to secure the power supply. SPARCstation 20 Service Manual • July 1996...
Page 83: Figure 8-3 Power Supply Captive Screws
Captive screw (2) Power Supply Captive Screws FIGURE 8-3 5. Connect the DC power connector to the system board ( FIGURE 8-4 6. Remove the wrist strap and replace the cover. See Chapter 7. 7. Connect the power cord to the rear of the system unit and the wall receptacle. 8.
Page 84: Led
ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. 3. Locate the LED at the shrink-wrapped end of the LED cable and the in-line connector ( FIGURE 8-5 SPARCstation 20 Service Manual • July 1996...
Page 85: Figure 8-5 Speaker/Led Cable Detail
In-line connector Speaker spade connector (large) Shrink-wrapped LED wires Speaker spade connector (small) Speaker/LED system Speaker/LED Cable Detail FIGURE 8-5 Note – Three tabs on the LED light pipe secure the LED to the right front corner of the chassis ( FIGURE 8-6 4.
Page 86: Figure 8-6 Led Light Pipe Detail
System right front corner Light pipe tabs Shrink-wrapped LED cable LED Light Pipe Detail FIGURE 8-6 SPARCstation 20 Service Manual • July 1996...
Page 87: Installing The Led
Shrink-wrapped In-line connector LED cable Speaker System board Speaker/LED connector Speaker/LED Cable FIGURE 8-7 Installing the LED Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. 1.
Page 88: Speaker
(see FIGURE 8-8 a. Insert the tip of a small flat-blade screwdriver between the speaker cover and the chassis. Press the top cover tab outward slightly to release it from the chassis slot. SPARCstation 20 Service Manual • July 1996...
Page 89: Figure 8-8 Speaker Cover Detail
b. Insert the screwdriver tip in one of the slots on the bottom of the speaker cover and press the lower cover tab up to release it from the chassis slot. Repeat this step to release the second lower cover tab. 4.
Page 90: Installing The Speaker
Note – Connectors and terminals are keyed to ensure proper connection. 2. Install the speaker in the opening on the system front. 3. Replace the two screws that secure the speaker to the chassis and proceed as follows ( FIGURE 8-8 SPARCstation 20 Service Manual • July 1996...
Page 91: Fan Assembly
a. Align the tabs on the speaker cover with the slots in the chassis. b. Press the speaker cover against the chassis; snap the speaker cover in place. 4. Detach the wrist strap and replace the cover. See Chapter 7. 5.
Page 92: Figure 8-10 Disconnecting The Fan Dc Power Connector
( FIGURE 8-11 d. Set the fan aside. Fan DC power connector Note: Cable restraints and SCSI data cables are not illustrated. Right side Front Disconnecting the Fan DC Power Connector FIGURE 8-10 SPARCstation 20 Service Manual • July 1996...
Page 93: Installing The Fan
Side mounting clip Fan assembly Metal drive bracket Bottom mounting clip Chassis bottom slot Note: Cable restraints and SCSI data cables are not illustrated. Front Right side Removing the Fan FIGURE 8-11 Installing the Fan Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat.
Page 94: Figure 8-12 Fan Assembly
Note – Position the fan assembly so that it does not interfere with the removal of the system hard disk drives. Clip Fan DC power connector Bottom mounting clip Fan Assembly FIGURE 8-12 2. Push the fan side mounting clip against the vertical edge of the chassis FIGURE 8-13 SPARCstation 20 Service Manual • July 1996...
Page 95: Figure 8-13 Mounting The Fan Assembly
Side mounting clip Locate side assembly mounting clip against this surface. Note: Cable restraints and SCSI data cables are not illustrated. Right Front side Mounting the Fan Assembly FIGURE 8-13 3. Place the notched tip of the fan installation tool over the side mounting clip and press down ( FIGURE 8-14 Chapter 8...
Page 96: Figure 8-14 Securing The Fan Assembly Using The Fan Installation Tool
5. Secure the fan DC harness beneath the cable restraint ( FIGURE 8-15 Note – Store any excess cabling under the cable restraint. 6. If a CD-ROM drive was removed, install it now. See “Installing a CD-ROM Drive” on page 124. SPARCstation 20 Service Manual • July 1996...
Page 97: Figure 8-15 Connecting The Fan Assembly Dc Power Connector
7. Detach the wrist strap and replace the cover. See Chapter 7. 8. Power on the system See Section “Turning On the Power” on page 6-47. Fan assembly Fan connector DC power connector Note: Cable restraints and SCSI data cables are not illustrated. Right Front side...
Page 98: Removing The Fan Dc Power Harness
CD-ROM drive DC power connector. The separate fan DC power harness has a two-wire fan DC power connector, a CD-ROM drive DC power connector, and a power connector for the optional CD-ROM drive connector ( FIGURE 8-17 SPARCstation 20 Service Manual • July 1996...
Page 99: Figure 8-17 Fan Dc Power Harness
Fan DC power connector CD-ROM drive DC power connector CD-ROM drive connector (optional) Fan DC Power Harness FIGURE 8-17 1. Remove power from the system. See “Removing Power from the System” on page 45. 2. Remove the cover and attach a wrist strap. See Chapter 7.
Page 100: Figure 8-18 Fan Dc Power Harness And Cable Restraint
Note: Cable restraints and SCSI data cables are not illustrated. Right side Front Fan DC Power Harness and Cable Restraint FIGURE 8-18 4. Disconnect the fan power connector from the DC power connector ( FIGURE 8-19 SPARCstation 20 Service Manual • July 1996...
Page 101: Figure 8-19 Disconnecting The Fan Power Connector From The Dc Power Connector
Fan assembly Fan power connector DC power connector Note: Cable restraints and SCSI data cables are not illustrated. Right Front side Disconnecting the Fan Power Connector from the DC Power Connector FIGURE 8-19 5. Lift the excess fan DC cable from the cable trough along the front of the chassis; remove the fan DC power harness ( FIGURE 8-20 6.
Page 102: Figure 8-20 Lifting Fan Dc Cable From The Cable Trough
Fan power connector Cable trough CD-ROM drive DC power connector Note: Cable restraints and SCSI data cables are not illustrated. Right side Front Lifting Fan DC Cable from the Cable Trough FIGURE 8-20 SPARCstation 20 Service Manual • July 1996...
Page 103: Installing The Fan Dc Power Harness
Fan DC power connector CD-ROM drive DC power connector power connector Note: Cable restraints and SCSI data cables are not illustrated. Front Right side Front Disconnecting the Fan Power Connector FIGURE 8-21 Installing the Fan DC Power Harness Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat.
Page 104: Figure 8-22 Cd-Rom Drive Dc Power Connector Location
3. Place the excess cable into the cable trough along the front of the chassis FIGURE 8-24 Note – Be sure an adequate amount of two-wire fan DC cable is exposed to allow fan connection. SPARCstation 20 Service Manual • July 1996...
Page 105: Figure 8-23 Connecting The Fan Dc Power Connector
Fan DC power connector CD-ROM drive DC power connector two-wire connector Note: Cable restraints and SCSI data cables are not illustrated. Front Right side Connecting the Fan DC Power Connector FIGURE 8-23 Chapter 8 Removing and Installing Subassemblies...
Page 106: Figure 8-24 Routing Excess Cables In Cable Trough
Note – Connectors and terminals are keyed to ensure proper connection. 5. Detach the wrist strap and replace the cover. See Chapter 7. 6. Power on the system. See “Turning On the Power” on page 47. SPARCstation 20 Service Manual • July 1996...
Page 107: Scsi Backplane
Fan assembly connector DC power connector Note: Cable restraints and SCSI data cables are not illustrated. Front Right side Fan DC Power Connector FIGURE 8-25 SCSI Backplane To remove and install the SCSI backplane, proceed as follows. Chapter 8 Removing and Installing Subassemblies...
Page 108: Removing The Scsi Backplane
Disconnect the DC power connector from the SCSI backplane socket. c. Disconnect the DC power connector clip from the DC power socket. d. Disconnect the SCSI data connector from the SCSI data socket. SPARCstation 20 Service Manual • July 1996...
Page 109: Figure 8-26 Scsi Backplane Sockets And Connectors
SCSI data socket DC power socket Single-connector drive sockets SCSI data connector DC power connector clip SCSI Backplane Sockets and Connectors FIGURE 8-26 5. Remove the two Phillips-head screws that secure the SCSI backplane to the plastic mounting bracket ( FIGURE 8-27 Note –...
Page 110: Figure 8-27 Scsi Backplane Screws
Squeeze the plastic bracket tabs together and release the SCSI backplane bracket from the slots that secure it to the sheetmetal chassis. SPARCstation 20 Service Manual • July 1996...
Page 111: Installing The Scsi Backplane
Long needlenose pliers Sheetmetal chassis SCSI backplane bracket Plastic bracket tab (2) SCSI Backplane Bracket Tabs FIGURE 8-28 Installing the SCSI Backplane Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface.
Page 112: Scsi Data Cable
See “Turning On the Power” on page 47. SCSI Data Cable The SPARCstation 20 system is configured with one of two chassis types: A chassis that supports the SunCD 2Plus drive (1-inch drive) A chassis that supports the SunCD 4 drive (1.6-inch drive) Removing and installing the SCSI data cable varies depending on the chassis.
Page 113: Figure 8-29 Internal Cables And Dc Power Connector (Suncd 2Plus Drive-Type Chassis)
2. Remove the cover and attach a wrist strap. See Chapter 7. Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. 3.
Page 114: Figure 8-30 Back Panel Sbus Slots And Captive Screws
SCSI data connector (P3) DC power connector clip DC power connector (P1) SCSI Backplane, SCSI Data, and DC Power Connectors FIGURE 8-31 7. Slide the system board back slightly to access the internal cables. SPARCstation 20 Service Manual • July 1996...
Page 115: Installing The Scsi Data Cable (Suncd 2Plus Drive-Type Chassis)
8. Remove the SunCD 2Plus CD-ROM drive, if installed. See “Removing a CD-ROM Drive” on page 123. 9. Disconnect the SCSI data connector (P3) from the SCSI backplane. 10. Free the SCSI data cable from the metal cable guides on the chassis bottom and from the plastic hooks on the system board card guide.
Page 116: Figure 8-32 Cable Guide Detail
( FIGURE 8-34 5. Replace any SBus cards (see FIGURE 8-37 See “Installing an SBus Card” on page 156. 6. Connect the following cables to the system board ( FIGURE 8-40 Speaker/LED cable SPARCstation 20 Service Manual • July 1996...
Page 117: Removing The Scsi Data Cable (Suncd 4 Drive-Type Chassis)
DC power connector SCSI data cable Diskette data cable (optional) 7. Detach the wrist strap and replace the cover. See Chapter 7. 8. Power on the system. See “Turning On the Power” on page 47. Removing the SCSI Data Cable (SunCD 4 Drive-Type Chassis) 1.
Page 118: Figure 8-33 Internal Cables And Dc Power Connector (Suncd 4 Drive-Type Chassis)
5. Pull the system board from the back of the chassis until it clears the plastic card guide ( FIGURE 8-34 Caution – Place the system board on an antistatic surface. 6. Remove the SunCD 4 CD-ROM drive. See “Removing a CD-ROM Drive” on page 123. SPARCstation 20 Service Manual • July 1996...
Page 119: Figure 8-34 Removing The System Board
Metal cable clips on chassis wall System board Card guide Removing the System Board FIGURE 8-34 7. Disconnect the following ( FIGURE 8-33 a. The SCSI data cable from the metal cable clips on the chassis wall, and from the plastic cable clips on the card guide. b.
Page 120: Installing The Scsi Data Cable (Suncd 4 Drive-Type Chassis)
FIGURE 8-33 6. Replace the SBus card. See “Installing an SBus Card” on page 156. 7. Tighten the two captive Phillips-head screws that secure the system board to the chassis rear ( FIGURE 8-30 SPARCstation 20 Service Manual • July 1996...
Page 121: Dc Power Harness
See “Turning On the Power” on page 47. DC Power Harness The SPARCstation 20 system is configured with one of two chassis types: A chassis that supports the SunCD 2Plus drive (1-inch drive) A chassis that supports the SunCD 4 drive (1.6-inch drive) Removing and installing the DC power harness varies depending on the chassis.
Page 122: Figure 8-35 Attaching A Wrist Strap To Back Panel And Removing The Power Supply
4. Remove any SBus cards. See “Removing an SBus Card” on page 152. 5. Disconnect the diskette data cable (optional), SCSI data cable, DC power connector, and the speaker/LED cable from the system board ( FIGURE 8-36 SPARCstation 20 Service Manual • July 1996...
Page 123: Figure 8-36 Internal Cables And Dc Power Connector (Suncd 2Plus Drive-Type Chassis)
Metal cable guide (2) Diskette data cable SCSI data cable Speaker/LED cable DC power connector System board Note: Figure illustrates SunCD 2Plus drive-type (1-inch drive) chassis only. Internal Cables and DC Power Connector (SunCD 2Plus Drive-Type Chassis) FIGURE 8-36 6. Loosen the two captive screws that secure the system board back panel to the chassis ( FIGURE 8-37 7.
Page 124: Figure 8-37 Back Panel Sbus Slots And Captive Screws
Back Panel SBus Slots and Captive Screws FIGURE 8-37 10. Remove the diskette drive. See “Removing a Diskette Drive” on page 127. 11. Free the SCSI cable from the metal cable guides ( FIGURE 8-38 SPARCstation 20 Service Manual • July 1996...
Page 125: Figure 8-38 Detail Of Cable Guide
Tie-wrap Metal cable markers guide Speaker/LED harness DC power harness SCSI data Drive bracket cable marker sheetmetal opening Card guide plastic hooks Detail of Cable Guide FIGURE 8-38 12. Remove the DC power harness from the metal cable guides ( FIGURE 8-39 13.
Page 126: Installing The Dc Power Harness (Suncd 2Plus Drive-Type Chassis)
Route the end of the DC power harness with connectors P1 and P3 through the sheetmetal opening in the drive bracket. Note – Be sure the tie wrap markers are in the proper position beneath the metal cable guides. SPARCstation 20 Service Manual • July 1996...
Page 127: Removing The Dc Power Harness (Suncd 4 Drive-Type Chassis)
b. Route the DC power harness through the metal cable guides. c. Route the SCSI data cable through the metal cable guides. d. Press the cable down between the drive bracket and the plastic card guide. 2. Connect P3 to the SCSI backplane ( FIGURE 8-39 3.
Page 128: Figure 8-40 Internal Cables And Dc Power Connector (Suncd 4 Drive-Type Chassis)
Note: Figure illustrates SunCD 4 drive-type (1.6-inch drive) chassis only. Internal Cables and DC Power Connector (SunCD 4 Drive-Type Chassis) FIGURE 8-40 Captive screw Captive screw Back Panel Captive Screws FIGURE 8-41 SPARCstation 20 Service Manual • July 1996...
Page 129: Figure 8-42 Removing The System Board
5. Pull the system board from the chassis back until the system board clears the plastic card guide ( FIGURE 8-42 System board Card guide Removing the System Board FIGURE 8-42 Caution – Place the system board on an antistatic surface. 6.
Page 130: Installing The Dc Power Harness (Suncd 4 Drive-Type Chassis)
Route the SCSI backplane DC power harness (labeled P3) under the plastic cable clips on the card guide to the SCSI backplane. c. Thread the diskette drive DC power harness (labeled P4) through the hole in the chassis wall with the diskette data cable. SPARCstation 20 Service Manual • July 1996...
Page 131: Diskette Drive Cable
9. Detach the wrist strap and replace the cover. See Chapter 7. 10. Power on the system. See “Turning On the Power” on page 47. Diskette Drive Cable The SPARCstation 20 system is configured with one of two chassis types: Chapter 8 Removing and Installing Subassemblies...
Page 132: Removing The Diskette Drive Cable (Suncd 2Plus Drive-Type Chassis)
3. Remove the CD-ROM drive. See “CD-ROM Drive” on page 123. 4. Perform Step 1 through Step 3 in “Removing a Diskette Drive” on page 127. 5. Locate the diskette drive cable ( FIGURE 8-43 SPARCstation 20 Service Manual • July 1996...
Page 133: Figure 8-43 Diskette Drive Cable Location
Diskette drive cable Diskette Drive Cable Location FIGURE 8-43 6. Pull the plastic cable tab to disconnect the diskette drive cable from the system board ( FIGURE 8-44 Plastic tab Connect to system board Diskette drive connector Diskette drive cable Plastic tab Diskette Drive Cable Plastic Tab FIGURE 8-44...
Page 134: Installing The Diskette Drive Cable (Suncd 2Plus Drive-Type Chassis)
Drive-Type Chassis) Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. SPARCstation 20 Service Manual • July 1996...
Page 135: Removing The Diskette Drive Cable (Suncd 4 Drive-Type Chassis)
Note – The replacement diskette drive cable should be folded at an angle to connect properly. See FIGURE 8-44 1. Work the end of the diskette drive cable that connects to the system board through the sheetmetal opening in the drive bracket and connect it to the system board ( FIGURE 8-45 Note –...
Page 136: Installing The Diskette Drive Cable (Suncd 4 Drive-Type Chassis)
Drive-Type Chassis) Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. SPARCstation 20 Service Manual • July 1996...
Page 137 1. Route the diskette drive cable in the system chassis. Note – The diskette drive cable should pass under the first metal cable clip in the chassis floor. 2. Connect the diskette drive cable to the system board ( FIGURE 8-46 3.
Page 138 SPARCstation 20 Service Manual • July 1996...
Page 139 Chapter 8 Removing and Installing Subassemblies...
Page 140 SPARCstation 20 Service Manual • July 1996...
Page 141: Storage Devices
Hard Disk Drive The SPARCstation 20 system uses 535-Mbyte, 1.05-Gbyte, and 2.0-Gbyte single-connector hard disk drives. Each disk drive connects to the SCSI backplane. A handle on each single-connector drive helps to install the hard disk drive into the SCSI backplane socket.
Page 142: Figure 9-1 Location Of Hard Disk Drives
The system software expects the disk drive to be at a specific SCSI address. 4. Press the plastic latch located beneath the handle at the rear of the drive to release the handle ( FIGURE 9-2 SPARCstation 20 Service Manual • July 1996...
Page 143: Figure 9-2 Single Connector Hard Disk Drive
Handle (partially lifted) Latch Single connector Handle pivot point Single Connector Hard Disk Drive FIGURE 9-2 5. Lift the drive handle up ( FIGURE 9-3 Note – When lifted, the drive handle pivots to disconnect the drive from the socket on the SCSI backplane.
Page 144: Installing A Hard Disk Drive
Installing a Hard Disk Drive Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. SPARCstation 20 Service Manual • July 1996...
Page 145 Note – The disk drive position determines the assigned SCSI address. When installed, the bottom disk drive is assigned SCSI address 3 and the top disk drive is assigned SCSI address 1. Note – No jumper settings are required for the hard disk drives. 1.
Page 146: Figure 9-4 Installing A Hard Disk Drive
Installing a Hard Disk Drive FIGURE 9-4 SPARCstation 20 Service Manual • July 1996...
Page 147: Cd-Rom Drive
CD-ROM Drive The SPARCStation 20 system is configured with one of two types of CD-ROM drives: a 1-inch SunCD 2Plus drive and a 1.6-inch SunCD 4 drive. To remove and install a CD-ROM drive, proceed as follows. Note – After removing a SunCD 2Plus or a SunCD 4 CD-ROM drive, be sure that the same drive-type is installed.
Page 148: Installing A Cd-Rom Drive
1. Ensure proper jumper installation as follows: a. For the SunCD 2Plus CD-ROM drive: at pins ID4, ID2, and Term power FIGURE 9-6 b. For the SunCD 4 drive: at pins ID4, ID2, and Term power ( FIGURE 9-7 SPARCstation 20 Service Manual • July 1996...
Page 149: Figure 9-6 Suncd 2Plus Rear View And Jumper Settings
Note – The two ID select jumpers set the SCSI address of the drive to 6. A parity jumper may also need to be installed ID select SCSI data interface connector Parity 4 2 1 Prevent / Allow Test SCSI bus terminators Term power DC input SunCD 2Plus Rear View and Jumper Settings...
Page 150: Diskette Drive
DC power cable Bracket Drive bracket SCSI data cable Installing a CD-ROM Drive FIGURE 9-8 Diskette Drive The optional internal diskette drive is located below the CD-ROM drive, adjacent to the power supply. SPARCstation 20 Service Manual • July 1996...
Page 151: Removing A Diskette Drive
To remove and install a diskette drive, proceed as follows. Note – If a CD-ROM drive is installed, it must be removed before a diskette drive can be removed or installed. Removing a Diskette Drive 1. Remove power from the system. See “Removing Power from the System”...
Page 152: Figure 9-10 Cd-Rom Drive Filler Panel
Use the screwdriver as a lever to move a diskette grommet forward, toward the center of the chassis ( FIGURE 9-11 6. Repeat Step 5 for other grommets to free the diskette drive. 7. Disconnect the power cable from the diskette drive ( FIGURE 9-11 SPARCstation 20 Service Manual • July 1996...
Page 153: Figure 9-11 Diskette Drive Power Cable
Disk drive power cable (P4) Diskette Drive Power Cable FIGURE 9-11 8. Disconnect the diskette drive data cable ( FIGURE 9-12 Chapter 9 Storage Devices...
Page 154: Figure 9-12 Diskette Drive Data Cable
9. Lift the diskette drive from the chassis; place the diskette drive on an antistatic surface ( FIGURE 9-13 10. Remove the Phillips screws and grommets; set screws and grommets aside FIGURE 9-13 SPARCstation 20 Service Manual • July 1996...
Page 155: Figure 9-13 Removing The Diskette Drive
Diskette drive Diskette drive power cable Diskette drive data cable Diskette drive mounts Removing the Diskette Drive FIGURE 9-13 Screw (4) Grommet (4) Diskette drive switch Installing Grommets and Setting the Diskette Drive Switch FIGURE 9-14 Chapter 9 Storage Devices...
Page 156: Installing A Diskette Drive
If the diskette drive does not have a switch on the side of the drive, it has a microswitch (SW4) on the printed circuit board (PCB) side of the drive. Set SW4 to the 0 position by pressing it towards the rear of the diskette drive FIGURE 9-16 SPARCstation 20 Service Manual • July 1996...
Page 157: Figure 9-16 Setting The Diskette Drive Microswitch
PCB side of drive Diskette drive microswitch Setting the Diskette Drive Microswitch FIGURE 9-16 c. Locate the two-wire diskette drive power cable labeled P4. Move the SCSI disk cable and the CD-ROM drive power cable away from the diskette drive opening ( FIGURE 9-17 FIGURE 9-17...
Page 158: Figure 9-19 Installing The Diskette Drive
Note – The diskette drive data cable must be positioned between the diskette drive and the metal chassis. Note – Push on the rear edge of the diskette drive chassis only. Do not push on exposed disk drive motors or connectors. SPARCstation 20 Service Manual • July 1996...
Page 159: Figure 9-20 Connecting The Diskette Drive Power Cable
4. Attach the diskette drive power and data cables to the diskette drive in the following sequence: a. Connect P4 ( FIGURE 9-20 Diskette drive power cable (P4) Connecting the Diskette Drive Power Cable FIGURE 9-20 Note – The top faces up when connected to the drive. b.
Page 160: Figure 9-21 Connecting The Diskette Drive Data Cable
FIGURE 9-22 b. Verify that the two posts align with the chassis holes. c. Squeeze the two tabs together and rotate the filler panel inward until the tabs snap into the chassis slots. SPARCstation 20 Service Manual • July 1996...
Page 161: Figure 9-22 Installing The Cd-Rom Drive Filler Panel
Tab (2) Post (2) Installing the CD-ROM Drive Filler Panel FIGURE 9-22 6. Detach the wrist strap and replace the cover. See Chapter 7. 7. Power on the system. See Chapter 6. Chapter 9 Storage Devices...
Page 162 SPARCstation 20 Service Manual • July 1996...
Page 163: System Board Overview
C H A P T E R System Board Overview This chapter contains descriptions of the system board. The following topics are presented in this chapter: Preventing Damage Caution – Use an antistatic mat when working with the system board. An antistatic mat contains the cushioning needed to protect the underside components, to prevent board flexing, and to provide antistatic protection.
Page 164: System Board Description
MBus module, SIMM, or chip) on a hard surface. Use a cushioned antistatic mat. See Chapter 12. Transport the system board in an antistatic bag. System Board Description identifies the major components of the SPARCstation 20 system board. FIGURE 10-1 SPARCstation 20 Service Manual • July 1996...
Page 165: System Board Frus
Diskette data connector SIMM slots SBus slots SCSI data connector Speaker/LED connector DC power connector connector NVRAM/TOD MBus slots OpenBoot PROM System Board FIGURE 10-1 System Board FRUs The following are system board FRUs: DSIMM VSIMM NVSIMM SBus card MBus module OpenBoot PROM NVRAM/TOD Chapter 10...
Page 166: Figure 10-2 Exploded View Of The System Board
Chapter 11 provides procedures for removing and replacing these components. See FIGURE 10-2 Auxiliary video board DSIMM SBus card MBus module VSIMM/NVSIMM Mbus clock speed jumper Serial port NVRAM jumpers OpenBoot PROM Exploded View of the System Board FIGURE 10-2 SPARCstation 20 Service Manual • July 1996...
Page 167: System Board And Component Replacement
C H A P T E R System Board and Component Replacement This chapter describes how to remove, replace, and configure the replacement parts. MBus Module The following paragraphs provide procedures for removing and installing a single- wide and a double-wide MBus module. To remove and install a single-wide and a double-wide MBus module, proceed as follows.
Page 168: Figure 11-1 Mbus Module Retainers
( FIGURE 11-3 7. Remove the card extractor from the MBus module. Note – Save the extractor for future use. 8. Place the MBus module on an antistatic surface. SPARCstation 20 Service Manual • July 1996...
Page 169: Figure 11-2 Extractor Installation On A Single-Wide Mbus Module
Card extractor MBus module Hot surface Extractor Installation on a Single-Wide MBus Module FIGURE 11-2 MBus module Hot surface Removing a Single-Wide MBus Module FIGURE 11-3 Chapter 11 System Board and Component Replacement...
Page 170: Installing A Single-Wide Mbus Module
3. Insert the back edge of the module between the metal (lower) and plastic (upper) tabs on the back panel. 4. Hold the MBus module corners and press down firmly until the module is seated into the slot. SPARCstation 20 Service Manual • July 1996...
Page 171: Removing A Double-Wide Mbus Module
Note – Be sure the MBus module is fully inserted into the MBus slot. If it is not, the card retainers may not lock over the edge of the module properly. Caution – Excessive force may bend or damage the pins. 5.
Page 172: Figure 11-6 Mbus Module Back Panel Screws And Washers
5. Hold each edge of the MBus module and pull up on the module until the connector is out of the slot ( FIGURE 11-7 6. Place the MBus module on an antistatic surface. Washer (2) Screw (2) MBus Module Back Panel Screws and Washers FIGURE 11-6 SPARCstation 20 Service Manual • July 1996...
Page 173: Installing A Double-Wide Mbus Module
MBus module (double-wide) Back panel Hot surface Removing a Double-Wide MBus Module FIGURE 11-7 Installing a Double-Wide MBus Module Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface.
Page 174: Figure 11-8 Installing A Double-Wide Mbus Module
Note – A double-wide MBus module installs and has a back plate like an SBus card. The connector on the MBus module should face the appropriate MBus module slot. Caution – An MBus module must be installed in MBus module slot 0 or the system will not work. SPARCstation 20 Service Manual • July 1996...
Page 175: Figure 11-9 Seating A Double-Wide Mbus Module Back Plate, Side View
System back panel slot MBus module MBus module back plate Seating a Double-Wide MBus Module back Plate, Side View FIGURE 11-9 Caution – Fingers should be on either side of the MBus module connector. Do not press both ends of the MBus module because only one connector is on the module. 3.
Page 176: Sbus Card
See Chapter 7. Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. SPARCstation 20 Service Manual • July 1996...
Page 177: Figure 11-11 Sbus Card Retainers
3. Unlock the retainers at the back edge of the SBus card ( FIGURE 11-11 Retainer (2) SBus card SBus Card Retainers FIGURE 11-11 4. Remove the screws and washers from the SBus card back plate ( FIGURE 11-12 Note – Save the screws and washers for later use. System back panel (cutaway) Washer (2)
Page 178: Figure 11-13 Installing The Card Extractor
5. Insert the extractor into the SBus card ( ) or insert two extractors into FIGURE 11-13 double-wide Sbus card ( FIGURE 11-14 Extractor Installing the Card Extractor FIGURE 11-13 Double-wide SBus card Removing a Double-Wide SBus Card FIGURE 11-14 SPARCstation 20 Service Manual • July 1996...
Page 179: Figure 11-15 Removing The Sbus Card Extractor
6. Hold each end of the extractor and pull up slowly until the connector is removed from the slot. Note – There are single-wide and double-wide SBus cards. shows a FIGURE 11-15 double-wide SBus card being removed. 7. Remove the card extractor from the SBus card as follows: a.
Page 180: Installing An Sbus Card
FIGURE 11-17 b. Remove the other side of the extractor, which should come out easily without bending. 5. Push the rear card retainers back on the system board ( FIGURE 11-17 FIGURE 11-18 SPARCstation 20 Service Manual • July 1996...
Page 181: Figure 11-17 Installing A Double-Wide Sbus Card
Note – show a double-wide SBus card and a single- FIGURE 11-17 FIGURE 11-18 wide SBus card, respectively, being installed. Installing a Double-Wide SBus Card FIGURE 11-17 SBus card SBus card connector Side view back panel Retainers Card back plate SBus slot Installing a Single-Wide SBus Card FIGURE 11-18...
Page 182: Figure 11-19 Sbus Card Back Panel Screws And Washers
8. Remove the wrist strap and replace the cover. See Chapter 7. 9. Power on the system. See Chapter 6. Washer (2) Screw (2) SBus Card Back Panel Screws and Washers FIGURE 11-19 SPARCstation 20 Service Manual • July 1996...
Page 183: Dsimms, Vsimms, And Nvsimms
DSIMMs, VSIMMs, and NVSIMMs The SPARCstation 20 system supports as many as eight dynamic single in-line memory modules (DSIMMs). DSIMMs are available in three capacities; 16-Mbyte, 32-Mbyte, and 64-Mbyte. In addition, the SPARCstation 20 system supports up to two video single in-line memory modules (VSIMMs) and one non- volatile SIMM (NVSIMM).
Page 184: Vsimm
DSIMM, Back View FIGURE 11-21 VSIMM SPARCstation 20 systems with the SX graphics option are equipped with a minimum of 4 Mbytes of video random access memory (VRAM). Physically, VRAM chips are grouped together as VSIMMs. Each VSIMM contains 4 or 8 Mbytes of video memory. Each VSIMM is a complete high-speed, high-resolution frame buffer that plugs into a memory slot located on the system board.
Page 185: Nvsimm
FIGURE 11-25 Caution – The installed SIMMs are specifically designed to operate in the SPARCstation 20 system. Do not remove DSIMMs, VSIMMs, or NVSIMMs from different Sun systems and install them in a SPARCstation 20 system. Chapter 11...
Page 186: Figure 11-25 Simm Slot Locations
3. Place an antistatic surface next to the system. Caution – Hot surface. Avoid contact. Surfaces are hot and may cause personal injury if touched. SPARCstation 20 Service Manual • July 1996...
Page 187: Installing A Simm
4. Using the eraser end of a pencil, move the ejection lever away from the SIMM to be removed ( FIGURE 11-26 SIMM SIMM Ejection levers SIMM Ejection Levers FIGURE 11-26 Note – Ejection levers are enlarged to show detail. 5.
Page 188: Figure 11-27 Dsimm, Back View
Mbyte DSIMM is previously installed in slot J0201, it must be removed from slot J0201 and installed in another unused DSIMM slot. Caution – The NVSIMM is specifically designed to operate in the SPARCstation 20 system. Do not remove a NVSIMM from a different Sun system and install it in a SPARCstation 20 system.
Page 189: Figure 11-28 Vsimm, Back View
Plastic cover Notch location VSIMM, Back View FIGURE 11-28 Caution – Once the battery is turned on, do not move or remove the jumper. Any data in the NVSIMM memory will be lost if the jumper is moved. 6. If installing an NVSIMM, proceed as follows ( FIGURE 11-29 a.
Page 190: Figure 11-30 Aligning The Nvsimm In The Slot, Back View
If the center notch is not properly aligned, the NVSIMM could be damaged when inserted. 8. Place the grooved surface of the insertion tool at a 90-degree angle on the upper edge of the SIMM ( FIGURE 11-31 FIGURE 11-32 SPARCstation 20 Service Manual • July 1996...
Page 191: Figure 11-31 Inserting A Dsimm
Grooved surface Insertion tool Inserting a DSIMM FIGURE 11-31 Grooved surface Insertion tool Inserting a VSIMM/NVSIMM FIGURE 11-32 9. Put the heel of each hand on each side of the insertion tool pushing surface. Press firmly with both hands on the tool until the SIMM snaps into place. Note –...
Page 192: Auxiliary Video Board
To remove and install an auxiliary video board (AVB), proceed as follows. Note – If installing a VSIMM in slot J0305, an AVB must be installed to provide video output for the second VSIMM. The SPARCstation 20 system can accommodate one AVB.
Page 193: Figure 11-33 Avb Installed
AVB Installed FIGURE 11-33 Back panel connector slot Removing the AVB FIGURE 11-34 Chapter 11 System Board and Component Replacement...
Page 194: Installing An Avb
Caution – Excessive force may bend or damage the pins. 3. Remove the wrist strap and replace the cover. FIGURE 11-33 4. Turn on system power. See Chapter 6. Back panel connector slot Installing the Auxiliary Video Board FIGURE 11-35 SPARCstation 20 Service Manual • July 1996...
Page 195: System Board
System Board The following sections describe how to remove and install the system board, and verify jumper settings Removing the System Board 1. Remove power from the system. See “Removing Power from the System” on page 45. 2. Remove the cover and attach the wrist strap. FIGURE 11-33 Caution –...
Page 196: Figure 11-36 Disconnecting Diskette, Scsi, Dc Power, And Speaker/Led Connectors
Disconnecting Diskette, SCSI, DC Power, and Speaker/LED Connectors FIGURE 11-36 5. At the chassis rear, loosen the lower two captive screws ( FIGURE 11-37 Captive screw Captive screw System Board Captive Screws FIGURE 11-37 SPARCstation 20 Service Manual • July 1996...
Page 197: Jumper Settings
6. Slide the system board toward the back of the chassis until it clears the plastic card guide ( FIGURE 11-38 7. Lift the back of the system board slightly. Slide the system board clear of the plastic card guide and out of the chassis. 8.
Page 198: Figure 11-39 System Board Jumper Settings
RS-232 mode (position A), refer to and proceed as follows: FIGURE 11-39 1. Using needlenose pliers, remove the 2-pin shunt from position B. 2. Using needlenose pliers, replace the 2-pin shunt to position A. SPARCstation 20 Service Manual • July 1996...
Page 199: Installing The System Board
Installing the System Board Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. 1. Position the system board over the back of the chassis so that the SIMM slots are facing the drive siderails and the chassis front.
Page 200: Figure 11-41 System Board Captive Screws
7. Connect the following to the system board ( FIGURE 11-42 Diskette connector (optional) SCSI connector DC power connector Speaker/LED connector 8. Remove the wrist strap and replace the cover. See Chapter 7. 9. Turn on system power. See Chapter 6. SPARCstation 20 Service Manual • July 1996...
Page 201: Openboot Prom
Diskette connector (optional) SCSI connector DC power connector Speaker/LED connector Connecting Diskette, SCSI, DC Power, and Speaker/LED Connectors FIGURE 11-42 OpenBoot PROM To remove and install an OpenBoot PROM, proceed as follows. Note – It is not necessary to transfer the OpenBoot PROM from an existing system board to a replacement system board.
Page 202: Removing An Openboot Prom
4. Use a DIP/IC extractor tool or a small flat-blade screwdriver to remove the OpenBoot PROM ( FIGURE 11-43 5. Place the OpenBoot PROM on an antistatic surface. OpenBoot PROM OpenBoot PROM Location FIGURE 11-43 SPARCstation 20 Service Manual • July 1996...
Page 203: Installing An Openboot Prom
Installing an OpenBoot PROM Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. 1. Hold the OpenBoot PROM by the edges and align the notch on the OpenBoot PROM with the notch on the socket ( FIGURE 11-44 Caution –...
Page 204: Nvram/Tod
See Chapter 7. Caution – Use proper ESD grounding techniques when handling components. Wear an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive components in antistatic bags before placing it on any surface. SPARCstation 20 Service Manual • July 1996...
Page 205: Installing A Nvram/Tod
3. Remove any SBus cards. See “Removing an SBus Card” on page 152. 4. Locate the NVRAM/TOD chip on the system board ( FIGURE 11-45 NVRAM/TOD socket NVRAM/TOD Location FIGURE 11-45 5. Grasp the NVRAM/TOD by the tabs on the NVRAM/TOD carrier and pull up on the carrier to extract the NVRAM/TOD.
Page 206: Figure 11-46 Nvram/Tod Orientation
4. Replace any SBus cards removed earlier. See “Installing an SBus Card” on page 156. 5. Detach the wrist strap and replace the cover. See Chapter 7. 6. Power on the system. See Chapter 6. SPARCstation 20 Service Manual • July 1996...
Page 207: Illustrated Parts Breakdown
C H A P T E R Illustrated Parts Breakdown This chapter lists the authorized replaceable parts for the SPARCstation 20 system. Note – The listed part numbers are correct as of the service manual publication date but are subject to change without notice. Consult your authorized Sun sales...
Page 208 1.44-Mbyte diskette drive (slim floppy) (SunCD 4 CD-ROM drive- 540-2854 type chassis) 535-Mbyte SCSI-2 disk drive w/ mounting kit 540-2443 1.05-Gbyte SCSI-2 disk drive w/ mounting kit 540-2560 2.1-Gbyte SCSI-2 disk drive w/ mounting kit 540-2699 Speaker 370-1579 SPARCstation 20 Service Manual • July 1996...
Page 209: Illustration Of Selected Frus
Illustration of Selected FRUs shows a top view of selected FRUs. shows an exploded view FIGURE 12-1 FIGURE 12-2 of the SPARCstation 20 system. shows the major components of the FIGURE 12-3 system board. shows standard external cables and shows...
Page 210: Figure 12-1 Selected Frus
Hard disk drive (2) (stacked) CD-ROM drive (top) DSIMM module slots SBus card slots NVSIMM/VSIMM AVB slot module slots Power supply MBus module slots System board NVRAM/TOD OpenBoot PROM Selected FRUs FIGURE 12-1 SPARCstation 20 Service Manual • July 1996...
Page 211: Figure 12-2 Sparcstation 20 System Exploded View
DC power harness SCSI data cable Diskette drive Speaker/LED cable Diskette cable Disk Fan DC drive (2) power Power cable Diskette supply filler panel External power cord Chassis SPARCstation 20 System Exploded View FIGURE 12-2 Chapter 12 Illustrated Parts Breakdown...
Page 212: Figure 12-3 Major Components Of The System Board
SBus card MBus module DSIMM module VSIMM or NVSIMM module Clock speed jumper Serial port NVRAM/TOD jumpers OpenBoot PROM Note: NVRAM/TOD carrier not illustrated. Major Components of the System Board FIGURE 12-3 SPARCstation 20 Service Manual • July 1996...
Page 213: Figure 12-4 Standard External Cables
External power cable Twisted-pair Ethernet cable Video cable Keyboard cable Microphone and cable Standard External Cables FIGURE 12-4 Chapter 12 Illustrated Parts Breakdown...
Page 214: Figure 12-5 Optional External Cables
IBM parallel printer cable Centronics parallel printer cable Serial port Y breakout cable SCSI cable Thick Ethernet AUI adapter cable Optional External Cables FIGURE 12-5 SPARCstation 20 Service Manual • July 1996...
Page 215: Product Specifications
A P P E N D I X Product Specifications This appendix provides product specifications for the SPARCStation 20 system and is divided into three parts: Physical specifications Electrical specifications Environmental specifications Physical Specifications lists the physical specifications for the SPARCStation 20 system.
Page 216: Electrical Specifications
Typical operating current 1.6 A at 100 VAC, 0.8 A at 240 VAC Typical operating power 120 W Maximum current 2.7 A at 100 to 120 VAC; 1.5 A at 200 to 240 VAC SPARCstation 20 Service Manual • July 1996...
Page 217 Electrical Specifications (17-inch Monitor) (Continued) TABLE A-3 Parameter Specification Maximum VA rating 290 VA Maximum power consumption 200 W Heat output 410 BTUs/hr Electrical Specifications (20-inch Monitor) TABLE A-4 Parameter Specification Nominal frequencies 50 Hz or 60 Hz (nominal) Nominal voltage range 100 to 120 VAC or 200 to 240 VAC Typical operating current 1.7 A at 110 VAC, 0.85 A at 220 VAC...
Page 218: Environmental Specifications
0 to 10,000 feet (0 to 3 km) Non-Operating Environment Temperature range -40˚ F to 149˚ F (-40˚ C to 65˚ C) Humidity 93% RH at 104˚ F (40˚ C) Altitude 0 to 40,000feet (0 to 12 km) SPARCstation 20 Service Manual • July 1996...
Page 219: Functional Description
See Chapter 1 for illustrations of the back panel. System Overview The SPARCstation 20 supports a system board, a power supply, up to two hard disk drives, a SunCD 2Plus or a SunCD 4 drive, and a diskette drive. A variety of SBus cards and MBus modules can be installed on the system board.
Page 220: System Board
Note – Installing a second VSIMM and NVSIMM reduces the maximum number of DSIMMs to six. AVB (one maximum, used with a second VSIMM) System Board shows a block diagram of the SPARCstation 20 system board. FIGURE B-1 SPARCstation 20 Service Manual • July 1996...
Page 221: Sbus Card
SCSI connector DSIMM 0 Memory bus COT 416 MBus Video 0 Video 1 MBus 1 SBus 1 SBus 3 MBus 0 SBus 0 SBus 2 DBRI SBus MSBI MACIO Aux video Audio on Floppy EEPROM board 85C30 82077 85C30 SCSI connector System Board Block Diagram FIGURE B-1 SBus Card...
Page 222: Mbus Module
Shared memory multiprocessor signals and transactions Write-invalidate cache coherency protocol In the SPARCstation 20 system, the MBus module can automatically switch from a 40-MHz frequency to a 50-MHz frequency, depending on the type of MBus module installed. Changing jumpers on the system board is not required.
Page 223: Table B-1 Memory Allocations
1 (max.) 2 (max.) DSIMM The SPARCstation 20 memory system has a 144-bit-wide data path. The 144-bit-wide path is divided into a 128-bit-wide data path and 16 bits of error correcting code (ECC). Through the Scalable Memory Controller (SMC), the 60-nanosecond DSIMMs receive control, address information, and data.
Page 224: Figure B-2 Dsimm Memory System
FIGURE B-2 The SPARCstation 20 system may contain one or more 32-Mbyte DSIMMs. The Solaris 1.1.1 Version B or later software environment for the SPARCstation 20 system supports up to eight 32-Mbyte DSIMMs or any combination of 16-Mbyte, 32-Mbyte, and 64-Mbyte DSIMMs.
Page 225: Figure B-3 Vsimm Memory System
The VSIMM contains a memory display interface (MDI) chip, a video buffer chip (VBC), and a digital-to-analog converter (DAC). There is also pixel clock generation circuitry on the VSIMM. The SPARCstation 20 uses 60-nanosecond VRAMs on the VSIMM. VRAM densities are supported by the SMC and are listed in TABLE B-3 illustrates the VSIMM memory system.
Page 226: Sbus-To-Scsi, Ethernet, And Parallel Interfaces
Parallel port The MACIO ASIC integrates three functions: Direct memory access (DMA) Local area network control for Ethernet (LANCE) Fast SCSI bus interface illustrates a functional block diagram of the MACIO ASIC. FIGURE B-4 SPARCstation 20 Service Manual • July 1996...
Page 227: Sbus-To-External Bus Interface
MACIO ASIC Clock LANCE chip Fast SCSI SCSI controller Parallel port Parallel port SBus MACIO ASIC Functional Block Diagram FIGURE B-4 SBus-to-External Bus Interface The SBus-to-external bus interface (SEC) ASIC provides the interface between the SBus and the external bus. The external bus connects to the following: Serial port chips (2) Audio chip Diskette drive controller...
Page 228: Clock Chip
One for the SBus-to-external bus interface (SEC) One for the SBus to DBRI Interface (DBRI) One for the SBus to external data interface (MACIO) One for SBus slots 0 and 1 One for SBus slots 2 and 3 SPARCstation 20 Service Manual • July 1996...
Page 229: System Board Connector Pinouts
A P P E N D I X System Board Connector Pinouts This appendix provides signal descriptions for the SPARCStation 20 system unit back panel connectors. through lists connector pin assignments TABLE C-1 TABLE C-8 and signal descriptions. An illustration of each connector is also provided.
Page 230 24-mA TTL AutoFeed AutoFeed* Error Error* 24-mA TTL Initialize Reset* 24-mA TTL Select in SlctIn* None Shield Shield None Shield Shield None Shield Shield None Shield Shield None Shield Shield * Active low signal SPARCstation 20 Service Manual • July 1996...
Page 231: Aui Connector
Shield * Active low signal AUI Connector The AUI connector is the bottom connector in the stacked pair of 26-pin connectors on the SPARCstation 20 system. lists connector pin assignments and signal TABLE C-2 descriptions for the parallel connector. AUI (bottom)
Page 232: Table C-2 Aui Connector Pin Assignments
N.C . None Not connected N.C . None Not connected N.C . None Not connected N.C. None Not connected N.C . None Not connected N.C . None Not connected N.C. None Ground Ground SPARCstation 20 Service Manual • July 1996...
Page 233: Keyboard And Mouse Connector
Keyboard and Mouse Connector lists connector pin assignments and signal descriptions for the keyboard TABLE C-3 and mouse connector. Keyboard and Mouse Connector FIGURE C-3 Keyboard/Mouse Connector Pin Assignments TABLE C-3 Function Level Signal Description Ground Ground Ground Ground +5 VDC Power Mouse In Input from mouse...
Page 234: Serial Ports A And B Connector
Not connected RS-232/423 Data terminal ready port B DTR B RS-232/423 Data carrier detect port B DCD B RS-232/423 Clear to send port B CTS B RS-232/423 Transmit data port B Xmit Data B SPARCstation 20 Service Manual • July 1996...
Page 235: Twisted-Pair Ethernet Connector
Serial Ports A and B Connector Pin Assignments (Continued) TABLE C-4 Function Level Signal Description RS-232/423 Receive/transmit clock port A TRxC A (pullup) RS-232/423 Receive data port B Rec Data B RS-232/423 Secondary/transmit clock RTxC A (receive) port RS-232/423 Receive/transmit clock port B TRxC B (pullup) RS-232/423...
Page 236: Scsi Connector
SCSI connector. TABLE C-6 SCSI Connector FIGURE C-6 SCSI Connector Pin Assignments TABLE C-6 Function Level Signal Description Ground None Ground Ground None Ground Ground None Ground Ground None Ground SPARCstation 20 Service Manual • July 1996...
Page 237 SCSI Connector Pin Assignments (Continued) TABLE C-6 Function Level Signal Description Ground None Ground Ground None Ground Ground None Ground Ground None Ground Ground None Ground Ground None Ground Ground None Ground Ground None Ground Ground None Ground Ground None Ground Ground None...
Page 238 Ground Ground None Ground Ground None Ground Ground Termination voltage Termpower None Ground Ground None Ground Ground Attention atn* None Ground Ground Busy bsy* Acknowledge ack* Reset rst* Message msg* Select sel* Control/data SPARCstation 20 Service Manual • July 1996...
Page 239: 13W3 Connector
SCSI Connector Pin Assignments (Continued) TABLE C-6 Function Level Signal Description Request req* Input/output * Active low signal 13W3 Connector lists the pin assignments and signal descriptions for the 13W3 connector. TABLE C-7 Note – Connector 13W3 is not enabled unless a VSIMM is installed into SIMM slot J0304.
Page 240: Audio Ports
Microphone (old) Microphone (new) Line-Out Line-In Left Channel Mono In Left Channel Left Channel Left Channel Ring Right Channel Microphone power Right Channel Right Channel Right Channel (Center) Shield Return Ground Return Return Return SPARCstation 20 Service Manual • July 1996...
Page 241: Headphone Connector
Headphone Connector The headphone is connector is for connecting a set of stereophonic headphones to the system for private listening of audio output. Microphone Icon FIGURE C-9 The microphone connector allows connection to the Sun Microphone II microphone. Audio Line-Out Icon FIGURE C-10 The audio line-out connector allows connection to a stereophonic amplifier and external loudspeakers.
Page 242 SPARCstation 20 Service Manual • July 1996...
Page 243: Scsi Addresses
A P P E N D I X SCSI Addresses This appendix describes the SCSI addresses for the two internal hard disk drives. Also described are the SCSI address conventions for optional SCSI peripherals. For complete SCSI address information regarding optional SCSI peripherals, see the installation manual for the particular SCSI peripheral.
Page 244: Table D-2 Scsi Addresses, Solaris 2.3 (Sunos 5.3) Operating Environment And Later Versions
CD-ROM, etc.) may be assigned any SCSI address from 0 to 6. Note – SCSI address 7 is reserved for the SCSI processor of the computer system or the SCSI host adapter card. SPARCstation 20 Service Manual • July 1996...
Page 245: Selected On-Board Diagnostics
A P P E N D I X Selected On-Board Diagnostics This appendix describes the OpenBoot PROM on-board diagnostics. To execute the on-board diagnostics, the system must be at the ok prompt. Caution – To execute the OpenBoot PROM on-board diagnostics from the ok prompt, the system must be shut down in an orderly manner.
Page 246: Test-All
Disks, tapes, and CDROMs are not tested by test-all. Tests are executed in the device tree (the device tree may be viewed with the show-devs command). To execute the test-all program, type the test-all command. test-all Command Output Message CODE EXAMPLE E-2 ok test-all SPARCstation 20 Service Manual • July 1996...
Page 247: Watch-Clock
watch-clock watch-clock reads a register in the NVRAM/TOD chip and displays the result as a seconds counter. During normal operation, the seconds counter repeatedly increments from 0 to 59 until interrupted by pressing any key on the keyboard. identifies the watch-clock command output message. CODE EXAMPLE E-3 watch-clock Command Output Message CODE EXAMPLE E-3...
Page 248: Watch-Net, Watch-Aui, Watch-Tpe, Watch-Net-All
..................Framing error CRC error X....The SPARCstation 20 system has two types of on-board Ethernet interfaces: 10Base- T (also called twisted-pair Ethernet or TPE) and 10Base5 (also called thick Ethernet or AUI). Only one on-board interface may be connected at a time. The system automatically selects which interface is connected and active.
Page 249 Note – Selecting a specific Ethernet interface to monitor may be controlled through these user-specific commands: watch-tpe monitors the TPE connection; watch- aui monitors the thick Ethernet connection; watch-net-all monitors Ethernet packets on all installed Ethernet interfaces, one at a time watch-tpe Command Output Message CODE EXAMPLE E-5 ok watch-tpe...
Page 250: Probe-Scsi, Probe-Scsi-All
The probe-scsi command transmits an inquiry command to internal and external SCSI devices connected to the SPARCstation 20 on-board SCSI interface. If a SCSI device is connected and powered up, the target address, unit number, device type, and manufacturer name is displayed.
Page 251: Test-Memory
identifies the probe-scsi command output message. CODE EXAMPLE E-7 identifies the probe-scsi-all command output message.: CODE EXAMPLE E-8 probe-scsi Command Output Message CODE EXAMPLE E-7 ok probe-scsi Target 3 Unit 0 Disk SEAGATE ST1480 SUN04245828 Copyright (c) 1991 Seagate All rights reserved. probe-scsi-all Command Output Message CODE EXAMPLE E-8 ok probe-scsi-all...
Page 252: Power-Off
MBus: 40.00 MHz SBus: 20.00 MHz CPU#0: 50.00 MHz SuperSPARC/SuperCache Multiprocessor module-info Command Output Message CODE EXAMPLE E-10 <#0> ok module-info MBus: 50.00 MHz SBus: 25.00 MHz CPU#0: 50.00 MHz SuperSPARC CPU#2: 50.00 MHz SuperSPARC SPARCstation 20 Service Manual • July 1996...
Page 253: Glossary
Reference is usually made to an address for the purpose of retrieving or storing information. AUI port Attachment unit interface port. (The port on the SPARCstation 20 system unit where the AUI adapter cable is connected. Auxiliary video board. Supports graphic capabilities when used with a second VSIMM option.
Page 254 A device that inputs data to a computer CPU and receives data from a computer CPU. keyboard Input device for entering data. keyboard port The port on the SPARCstation 20 system unit where the keyboard cable is connected. LANCE Local area network control for Ethernet. Light emitting diode.
Page 255 Forth Toolkit. If disaster happened to your operating system, the Monitor automatically starts. Monitor 2) A video display unit that is part of the SPARCstation 20 system. It is not the same as a terminal. MSBI MBus-to-SBus interface.
Page 256 A device that consists of a video display and keyboard. Used to type and display information. A terminal may be connected to either of the RS-423/RS-232 serial interface ports on the backpanel of the SPARCstation 20 system. Time of day.
Page 257 216 null modem, 19 ports, 216 serial connection, 19 trough, 77, 80 audio line-in connector, 217 cables, attaching, SPARCstation 20, 135 audio line-out connector, 217 captive screw, 56, 58 AUI, 224 backpanel, 175 connector, 207 system board, 172, 176...
Page 258 (P4), 134 controller, SCSI, 34 removing, 127, 131 corner screw, 49 setting microswitch, 133 cover setting switch, 131 removing, 50 unseating grommets, 132 replacing, 51 diskette drive cable, 107 speaker, 64 SPARCstation 20 Service Manual • July 1996...
Page 259 109 SPARCstation 20 system, 3, 187 plastic tab, 109 system board, 142 proper fold, 111 external pulling through drive bracket opening, 110 cables document organization, xix optional, 190 standard, 189 documentation, SunVTS, 15 options, 7 double-wide MBus module installing, 150...
Page 260 49 interior view of system, 3 locking MBus module retainers, 152 internal access, 49 cables (SunCD 2Plus drive-type chassis), 89, 99 (SunCD 4 drive-type chassis), 94, 104 MACIO ASIC, 202 SPARCstation 20 Service Manual • July 1996...
Page 261 functional block diagram, 203 CD-ROM drive connector, 74 external cables, 190 major components system board, 188 options external, 7 mat, antistatic, 40 internal, 6 MBus module, 143 SCSI, 7 backplane screws, 148 SX graphics, 6 backplane washers, 148 output voltage, 29 card extractor, 144 locking, retainers, 152 overview...
Page 262 1 cover, 51 speciﬁcations, 191 requirements operating systems, 6 safety, 39 software, 6 restarting system while troubleshooting, 46 rear view SunCD 2Plus, 125 RS-423 mode, 174 SunCD 4 drive, 125 SPARCstation 20 Service Manual • July 1996...
Page 263 33 2.3, 6 device, 14, 220 spade connectors, 66 target ID, 220 speaker, 65 terminator, 34 SPARCstation 20 system, 2 SCSI backplane, removing, 84 basic, 6 SEC ASIC, 203 conﬁgurations, 6 functional block diagram, 204 exploded view, 3...
Page 264 SunDiag system exerciser, 11, 14 disk3, 13 SunOS drive, 47 4.1.3_U1, 6 drives, 47 5.3, 6 ﬂoppy, 12 SunVTS keyboard, 13 documentation, 15 loopback, 12 kernel, 15 memory, 13 tty, 16 module-info, 14 SPARCstation 20 Service Manual • July 1996...
Page 265 net, 12 net-aui, 12 uniprocessor module-info command output net-tpe, 12 message, 228 POST, 20 UNIX commands, xxiii power supply, 29 user interface, SunVTS, 15 SBus cards, 47 screen, 12 scsi, 12 supported, 12 system board, 31 video output tape, 13 failure, 28 tape0, 13 port, 28...
Page 266 50 SPARCstation 20 Service Manual • July 1996...

Sun Microsystems SPARCstation 20 Service Manual

1 Product Description

2 Troubleshooting Overview

3 Power-On Self Test (POST)

4 Troubleshooting Procedures

5 Safety and Tools Requirements

6 Power on and off

7 Internal Access

8 Removing and Installing Subassemblies

9 Storage Devices

10 System Board Overview

11 System Board and Component Replacement

12 Illustrated Parts Breakdown

Product Specifications

Functional Description

Quick Links

Troubleshooting

Related Manuals for Sun Microsystems SPARCstation 20

Summary of Contents for Sun Microsystems SPARCstation 20