Texas Instruments 990 Manual page 9

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945424-9701
LIST OF TABLES (Continued)
Table Title
Page
1-5 Universal Keyboards Outputs in Hexadecimal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... .1-29
1-6 Test Data Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-52
1-7 Selected Test Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-52
1-8 Instruction Decoder Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-57
1-9 Byte Selector Truth Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-58
1-10 Model 911 VDT Character Decoder ROM Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-88
1-11 Model 911 VDT Row Decoder ROM Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-89
1-12 Model 911 VDT Sync Decoder ROM Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-90
2-1 Model 911 VDT Fault Isolation Procedures Keyboard ............................. 2-11
2-2 Power/Logic PWB Troubleshooting Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
2-3 Power/Logic PWB Fault Isolation Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
24 VDT Controller Standard Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-18
2-5 VDT Controller Troubleshooting Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-19
2-6 VDT Controller Preliminary Fault Isolation Procedures ............................ 2-20
2-7 Fault Isolation Procedures When Unable to Load Diagnostic ......................... 2-21
2-8 Fault Isolation Procedures for Apparent CRU Interface Problems ...................... 2-22
2-9 Fault Isolation Procedures for Apparent Timer Problems .......................... .2-25
2-10 Fault Isolation Procedures for Apparent Memory Failure .......................... .2-27
2-11 Fault Isolation Procedure for Apparent Alarm Problems ............................ 2-28
2-12 Fault Isolation Procedures for Apparent Keyboard-Related Problems ................... 2-30
2-13 Fault Isolation of Apparent Cursor Address Problems .............................. 2-32
2-14 Fault Isolation of Problems Indicated by Self-Test LED ............................ 2-33
2-15 Fault Isolation Procedures for CRT Monitor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-34
ix
Digital Systems Division