250
Machine-Independent Computer Programming
TABLE XIII
MACHINE LANGUAGE INSTRUCTION REPERTOIRE OF THE
UNIVAC M-46O COUNTESS COMPUTER
FF Function FF Function
00 Illegal 40 Enter logical product
01 Shift Q right 41 Add logical product
02 Shift A right 42 Subtract logical product
03 Shift AQ right 43 Mask comparison
04 Compare 44 Replace logical product
05 Shift Q left 45 Replace add logical product
06 Shift A left 46 Replace subtract logical product
07 Shift AQ left 47 Store logical product
10 Enter Q register 50 Selective set
11 Enter accumulator 51 Selective complement
12 Enter B register 52 Selective clear
13 Enter C register 53 Substitute
14 Store Q register 54 Replace selective set
15 Store accumulator 55 Replace selective complement
16 Store B register 56 Replace selective clear
17 Store C register 57 Replace substitute
20 Add 60 Arithmetic jump
21 Subtract 61 Manual jump
22 Multiply 62 Input jump
23 Divide 63 Output jump
24 Add replace 64 Arithmetic return jump
25 Subtract replace 65 Manual return jump
26 Q add 66 Input return jump
27 Q subtract 67 Output return jump
30 Load A add Q 70 Initiate repeat
31 Load A subtract Q 71 Index skip
32 Add Q and store 72 Index jump
33 Subtract Q and store 73 Initiate input transfer
34 Replace add Q 74 Initiate output transfer
35 Replace subtract Q 75 Initiate input buffer
36 Replace add one 76 Initiate output buffer
37 Replace subtract one 77 Illegal.
Here are MikeVanEmmerik's guesses for the j, k, and b fields:
| j = branch condition |
|---|
| 0 | never |
| 1 | ? |
| 2 | |
| 3 | |
| 4 | equal to 0 |
| 5 | not equal to 0 |
| 6 | >= 0 |
| 7 | < 0 |
| k = operand interpreter |
|---|
| 0 | immediate yyyyy |
| 1 | indirect memory m[m[yyyyy]] ? |
| 2 | |
| 3 | direct memory m[yyyyy] |
| 4 | |
| 5 | |
| 6 | |
| 7 | |
| b = index designator |
|---|
| 0 | no index |
| 1 | b |
| 2 | |
| 3 | |
| 4 | |
| 5 | |
| 6 | |
| 7 | |
See also
CategoryDecompilation