10/89 Device handbook A
PLUS
with / without LED display
,
157
679-19, 04/2016
3.3.2 Logic components
The logic outputs are calculated via a two level logical combination of states, which are present at the
inputs. Usable components are AND, OR and XOR gates as well as their inversions NAND, NOR and
XNOR.
The principal function of the logical gates is given in the following table, for simplicity shown for gates with
two inputs only.
function
symbol
older symbols
truth table
plain text
ANSI 91-1984
DIN 40700 (alt)
AND
A
B
Y
0
0
0
0
1
0
1
0
0
1
1
1
Function is true if all input
conditions are fulfilled
NAND
A
B
Y
0
0
1
0
1
1
1
0
1
1
1
0
Function is true if at least
one of the input
conditions is
not
fulfilled
OR
A
B
Y
0
0
0
0
1
1
1
0
1
1
1
1
Function is true if at least
one of the input
conditions is fulfilled
NOR
A
B
Y
0
0
1
0
1
0
1
0
0
1
1
0
Function is true if
none
of
the input conditions is
fulfilled
XOR
A
B
Y
0
0
0
0
1
1
1
0
1
1
1
0
Function is true if exactly
one of the input
conditions is fulfilled
XNOR
A
B
Y
0
0
1
0
1
0
1
0
0
1
1
1
Function is true if all of
the input conditions are
fulfilled or all conditions
are not fulfilled
The logic components of the first level may combine up to three, the components of the second level up to
four input conditions. If individual inputs are not used, their state is automatically set to a condition which
has no influence on the logic result.