M74HC181
TRUTH TABLE 2
SELECTION
S3 S2 S1 S0
M = H LOGIC
FUNCTIONS
ACTIVE HIGH DATA
M = L ARITHMETIC OPERATIONS
Cn = H (no carry)
Cn = L (with carry)
L L L L F=A
L L L H F=A+B
L L H L F = AB
L L H H F=0
L H L L F = AB
L H L H F=B
L H H L F=A⊕B
L H H H F = AB
H L L L F=A+B
H L L H F=A⊕B
H L H L F=B
H L H H F = AB
H H L L F=1
H H L H F=A+B
H H H L F=A+B
H H H H F=A
F = A minus 1
F=A+B
F=A+B
F = minus 1 (2’s Compl)
F = A plus (AB)
F =A + B plus AB
F = A minus B minus 1
F = AB minus 1
F = A plus AB
F = A plus B
F = (A + B) plus AB
F = AB minus 1
F = A plus A*
F = (A + B) plus A
F = (A + B) plus A
F = A minus 1
F = A plus 1
F = (A + B) plus 1
F = (A + B) plus 1
F = Zero
F = A plus AB plus 1
F = (A + B) plus (AB) plus 1
F = A minus B
F = AB
F = A plus AB plus 1
F = A plus B plus 1
F = (A + B) plus AB plus 1
F = AB
F = A plus A plus 1
F = (A + B) plus A plus 1
F = (A + B) plus A plus 1
F=A
* : Each bit is shifted to the next more significant position.
FIGURE 2
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