Page 188 -

243_MasterPieces_04a.qxd 4/18/03 7:05 PM Page 160

160 Masterpiece 4 • PneumADDic II

Figure 1.8 Pneumatic AND Gate in All Possible States

0 0

0

0 1

0

1 0

0

1 1

1

The OR Gate
The OR operator has two input values and one result.Table 1.4 shows all possible com-
binations of inputs to the OR operator, and the output result. In English,Table 1.4 states,
“If Input 1 is 1 OR Input 2 is 1 (OR both), the output is 1. Otherwise the output is 0.”
Figure 1.9 shows the OR gate in all possible states. Like the AND gate, it uses two pis-
tons as inputs, and a switch as the output. When either piston is expanded (in the 1 state),
the pneumatic switch is flipped to the right (the 1 state), otherwise the switch is flipped
to the left (the 0 state).