Line Labels
+
+
+1
-1
=0,-l
=9,+1
=15,+1
An
c
D
Dn
EN
F
G
J
K
LD
PS
R
RD
S
SEL
SER
T
WR
Yn
3-ST
(placed by
function label)
Shift Left (or up)
Shift Right (or down)
Count Up
Count Down
Borrow Output
Carry Output (Decimal Counter)
Carry Output (Binary Counter)
nth Address Bit (ROM, RAM)
Clock Input
Data or Delay Input (Flip-Flop)
nth Data Bit Input
Enable
3-State Enable Input (See “Dependency”)
Gating Input (See “Dependency”)
J-K Flip-Flop J Input
J-K Flip-Flop K Input
Load Enable Input (Synchronous)
Preset Input (Asynchronous)
Reset or Clear Input
Read Enable Input (RAM, ROM)
Set Input
Line or Function Select Input
Serial Data Input (Shift Register)
Trigger Input (Monostable)
Write Enable Input (RAM)
nth Data Bit Output or I/O
3-State
Figure 6. Schematic Symbols for Digital Integrated Circuits (4 of 7)
16 General Information