help with non masm machine language question

[gammaman]

Given the following location and instruction, find AC, PC and IR.   The ones that are filled in I think I have correct, please check.  The ones with a question mark, I have no clue, please help.   

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Location        Instruction           AC           PC             IR
100                  CLA                 0000        101           7800
101                  LDA 106              ?          102              ?
102                  BUN 104              ?          104              ?
103                  HLT                    ?           104           7001
104                  ADD 107              ?          105               ?
105                  BUN 103              ?          103                ?
106                  31FA                   ?           ?                   ?
107                  6FC5                   ?           ?                    ?


Here are the computer instructions

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AND   0xxx   8xxx       AND memory word to AC
ADD   1xxx   9xxx       Add memeory word to AC
LDA   2xxx    Axxx       Load mem to AC
STA   3xxx   Bxxx        store content of ac in mem
BUN    4xxx   Cxxx       branch unconditionally
BSA    5xxx   Dxxx       branch and save return address
ISZ     6xxx   Exxx       increment and skip if zero

CLA     7800     clear ac
CLE      7400    clear e
CMA     7200    comliment ac
CME     7100    compliment e
CIR      7080    circulate right ac and e
CIL      7040    circulate left ac and e
INC      7020   increment ac
HLT      7001    halt computer


[Jimg]

This looks suspiciously like code I used to write on an IBM mainframe about 30 years ago, but nothing like masm.  Why are you asking here?

[gammaman]

This code was made up by the author of my text book (Morris Mano).  I am asking here because I need help with this and do not know where else to ask.

[dedndave]

it's not made up - it's IBM AIX
c'mon Matt - this is really easy stuff
AC is the accumulator - so - if they do an "LDA 106", then the AC becomes the data at 106 which is 31FA
the HLT instruction essentially loops on itself - so the PC points back to the halt
the answers for the data lines at the bottom, i would put N/A, as they are not executed
IR = instruction register - that one almost does itself
you should be able to fill in the rest

[gammaman]

I understand now, thank you.  I do not know who designed this forum, but did anyone ever consider implementing a thanks button that users can click to thank others for their useful posts? 

[gammaman]

I got a bit more of the table filled out.  I am still unsure of some of the values for AC.

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Location        Instruction           AC           PC             IR
100                  CLA                 0000        101           7800
101                  LDA 106              ?          102           2106
102                  BUN 104              ?          104           4104
103                  HLT                    ?           104           7001
104                  ADD 107         6FC5          105           1105
105                  BUN 103         6FC5          103            4103
106                  31FA                 N/A          N/A              N/A
107                  6FC5                 N/A           N/A              N/A