HP 5363B, Руководство по эксплуатации и обслуживанию

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M od e l
5 36 3 8
S e rvice
EXAMPLE
5
DEV I CE # 1
FU NCTION TABLE
A B V
H H H
H
L L
L H L
L L L
P O SI T I V E L O G I C .
DEVICE #1
N EG AT I V E L O G I C.
DEVICE # 1
DEVICE # 2
F U NCTI ON TABLE
A B V
H H H
H
L H
L
H H
L L L
DEVICE #2
:=G>--V
DEVICE #2
Ass u m e two devices h avi ng the following function
tables.
By assi g n i n g the relat i o n s h ips H
==
1 ,
L
==
°
at both
i n put a n d output. Device #1 can perfor m the A N D
f u nction a n d Device # 2 can perform the O R f u n ction.
Such a consi stent ass i g n ment i s referred t o as
positive logic.
Alternatively, b y assig n i ng the relat i o n s h i p H
=
0;
L
==
1 at both i n p ut and output, Device # 1 can per­
form the OR f u nction and Device #2 can perfo rm the
A N D fu nction. S u c h a consistent ass i g n ment is re­
ferred to as negative logic.
8 -4 5 .
M
I X E D L O G I C . T h e use of the p o l a ri t y i n d i cator symbol o n s o m e i n p u ts
�
a ut o m a t i ca l l y i n vokes a m i xed-l og i c c o n ve n ti o n . T h i s i s , p o s i t i ve l o g i c i s u sed at t h e i n p uts
a n d o u t p u t s that h a ve pol a rity i n d i cators .
EXAMPLE 6
F U N C T I O N TAB L E
A B Z
H
H L
H L H
L H H
L L
H
EXAMPLE
7
F U N C T I O N TAB L E
A B Z
H H
L
H L L
L H L
L L
H
T h i s may be shown
either of two ways: :=Er-z
:�z
T h i s may be shown
ei ther of two ways:
:�z
:�z
Note the eq u iva lence of these symbols to Exa m ples
1 and 2 a n d the fact that the function table is a
positive-log ic translation
r
H
=
1 ,
L =
° of t h e N A N D
truth table. and a l so note t h a t the function table i s
t h e negative- l o g i c translation .
H
=
0, L
=
1 of the
NOR truth table, g i ven i n Example 3.
Note the equ ivalence of t h ese symbols to Exa m ples
3 and 4 and the fact that the f u n ct i o n table is a
posi tive-log ic translation
H
=
1 . L
==
° of t h e NOR
truth table, and a l so note that the f u nction table i s
the negative- log ic translation !
H
=
0 ,
L
=
1
'
of t h e
N A N D t r u t h t a b l e . g iven i n E x a m p l e
1 .
8-9