
Operating Mode Table
Controls
Outputs
E1 E2 S1 S0
Qn
HXXX
Latched (Note 1)
XHXX
Latched (Note 1)
LLLL
LLHL
L L LH
D0x
D0x + D1x
L
L LHH
H = HIGH Voltage Level
L = LOW Voltage Level
X = Don’t Care
Note 1: Stores data present before E went HIGH
D1x
Logic Diagram
Truth Table
Inputs
Outputs
MR E1 E2 S1 S0 D1x D0x Qx
Qx
HXXXXXX H
L
L L LHHHX
L
H
L L LHH L X H
L
L L L L LXH
L
H
L L L L LXL
H
L
L L L LHXX H
L
L L LHLHX
L
H
L L LHLXH
L
H
L L LHL L L
H
L
L H X X X X X Latched (Note 1)
L X H X X X X Latched (Note 1)
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