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# Lab 6, Task 2 (partial arithmetic logic unit)
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Here is the truth table from the lab page:

       | op | x | y || r1 | r0 |
       |----|---|---||----|----|
       | 0  | 0 | 0 || 0  | 0  |
       | 0  | 0 | 1 || 0  | 1  |
       | 0  | 1 | 0 || 0  | 1  |
       | 0  | 1 | 1 || 1  | 0  |
       | 1  | 0 | 0 || 0  | 0  |
       | 1  | 0 | 1 || 0  | 0  |
       | 1  | 1 | 0 || 0  | 0  |
       | 1  | 1 | 1 || 0  | 1  |

The column for r1 only has one 1, so the minterm expansion for r1 is simple:
       __
  r1 = op*x*y

  (note that we're using - for NOT and * for AND)


The column for r0 has three 1s, so the minterm expansion for r0 has 3 terms:
       __ _     __   _
  r0 = op*x*y + op*x*y + op*x*y