ELECTRONICS TROUBLESHOOTING 

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Computer Interfacing

Directions: Step through the program already prewritten below (First  "Burn Prom" and "Load RAM") . Set (check) switches S1 thru S8 as desired and observe how single stepping thru entire program causes LED's to illuminate in accordance with switch settings.   

The voltmeter can be connected to P1-1 thru P1-18 or TP1 thru TP5 and will sample the voltage at the end of each Single Step cycle (See Note  11 on specification page.) This page has no fault and can be used as an operational baseline as needed in troubleshooting.      

Computer Interface Schematic- Click Here! 
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COMPUTER CONTROL
 (CPU, ADDER, COMPARATOR)

Register A        Carry       
Register B        A>B       Program Counter
Accumulator    A=B        Instruction Register
                                    A<B
  Data Bus  Address Bus  
--------------------PROM(8X64)----------------RAM(8X16)---------
00      16       32      48      64
01      17       33      49      65
02      18       34      50      66
03      19       35      51      67
04      20       36      52      68
05      21       37      53      69
06      22       38      54      70
07      23       39      55      71
08      24       40      56      72
09      25       41      57      73
10      26       42      58      74
11      27       43      59      75
12      28       44      60      76
13      29       45      61      77
14      30       46      62      78
15      31       47      63      79

      

                                       

 

             Interface Assy No.1

LED1            S1           P1-1         Voltmeter       
LED2            S2           P1-2       
LED3            S3           P1-3       
LED4            S4           P1-4        TP1
LED5            S5           P1-5        TP2
LED6            S6           P1-6        TP3
LED7            S7           P1-7        TP4
LED8            S8           P1-8        TP5
                                                P1-9 Not Used          
                                               P1-10
                                               P1-11 
                                               P1-12  
                                               P1-13  
                                               P1-14  
                                               P1-15  
                                               P1-16  
                                               P1-17  
                                               P1-18  
                                                                                                                                                                               

 

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External Links Below

Also See RS-232

OR
Input/Data Acquisition System Design for Human Computer Interfacing

Or
Networks