Gate Symbols; Qualifying Symbols For Inputs And Outputs - HP 5334B Service Manual

Table 8-1. General Qualifiing Symbols (Contittued)
8-53. Gate Symbols
8-54. The ANSIIIEEE standard defines new symbols for the basic gate functions, but also permits the use of
the MIL-STD-806B symbols for these gates, as shown in Figure 8-2. In this manual, the distinctively shaped AND-
gate, OR-gate, Exclusive-OR-gate, and Inverter symbols will be used for those gates which are not part of a com-
plex logic device. The new symbols will be used for those gates embedded within a logic symbol, signifying that
they are one element of more complex logic device.
Example
SN74LS595
SN54LS590
SN74LS668
SN74187
SN74170
SN74LS222
SN74AS877
SN74LS608
Symbol
SRGm
CTRm
CTR DlVm
RCTRm
ROM
RAM
Fl FO
1=0
0
AND
>
E
qTE
-
q-k
EXCLUSIVE-OR
-
-
4-k
INVERTER
{ T k
(LOGIC NEGATION)
INVERTER
4 - b
(POLARITY INDICATION)
LPPLLe
Description
Shift register. m
=
number of bits.
Counter. m
=
number of bits; cycle length
=
2m.
Counter with cycle length
=
m.
Asynchronous (ripple-carry) counter; cycle length
=
2m.
Read-only memory.
Random-access readlwrite memory.
First-in, firt-out memory
Element powers up cleared to 0 state.
Highly complex function; "gray box" symbol with limited detail shown
under special rules.
Figure 8-2. Gate Sytnbols
8-55. Qualifying Symbols for Inputs and Outputs
8-56. The symbols shown in Table 8-2 are used to indicate the external states of both gate and complex logic
devices, and their relationship to internal states.
HP 5334B
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Service Manual
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