100313
真值表
输入
E
H
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
D
a
X
L
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
D
b
X
L
L
L
L
H
H
H
H
L
L
L
L
H
H
H
H
D
c
X
L
L
H
H
L
L
H
H
L
L
H
H
L
L
H
H
D
d
X
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
O
1a
, 0
2a
H
L
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
O
1a
, O
2a
L
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
输出
O
1b
, 0
2b
O
1b
, 0
2b
O
1c
, 0
2c
O
1c
, 0
2c
O
1d
, 0
2d
O
1d
, 0
2d
H
L
L
L
L
H
H
H
H
L
L
L
L
H
H
H
H
L
H
H
H
H
L
L
L
L
H
H
H
H
L
L
L
L
H
L
L
H
H
L
L
H
H
L
L
H
H
L
L
H
H
L
H
H
L
L
H
H
L
L
H
H
L
L
H
H
L
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
=
高电压电平
L
=
低电压电平
X
=
不在乎
www.fairchildsemi.com
2
