Connection Diagrams (Continued)
Storage from
Bus to Register
Real Time Transfer
A-Bus to B-Bus
DS100209-7
FIGURE 3.
DS100209-5
FIGURE 1.
Transfer from
Register to Bus
Real Time Transfer
B-Bus to A-Bus
DS100209-8
DS100209-6
FIGURE 4.
FIGURE 2.
Inputs
Data I/O
Function
(Note 1)
OE DIR CPAB CPBA SAB SBA A0–A7 B0–B7
H
H
H
L
L
L
L
L
L
L
L
=
X
X
X
H
H
H
H
L
H or L H or L
X
X
X
L
X
X
X
X
X
X
X
L
Isolation
N
X
Input
Input Clock An Data into A Register
Clock Bn Data into B Register
N
X
X
X
X
An to Bn — Real Time (Transparent Mode)
N
L
Input Output Clock An Data into A Register
A Register to Bn (Stored Mode)
H or L
X
H
H
X
X
X
X
N
X
Clock An Data into A Register and Output to Bn
Bn to An — Real Time (Transparent Mode)
Output Input Clock Bn Data into B Register
X
X
X
X
X
N
L
L
L
H or L
H
H
B Register to An (Stored Mode)
N
L
Clock Bn Data into B Register and Output to An
H
L
X
HIGH Voltage Level
=
LOW Voltage Level
Immaterial
=
N =
LOW-to-HIGH Transition
Note 1: The data output functions may be enabled or disabled by various signals at the OE and DIR inputs. Data input functions are always enabled; i.e., data at
the bus pins will be stored on every LOW-to-HIGH transition of the appropriate clock inputs.
3
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