54abt16646 National Semiconductor Corporation, 54abt16646 Datasheet - Page 3

• Manufacturer Part Number: 54abt16646
• Description: 16-bit Transceivers And Registers With Tri-state Outputs
• Manufacturer: National Semiconductor Corporation

OE
H
H
H
L
L
L
L
L
L
L
L
Function Table
H = HIGH Voltage Level
L = LOW Voltage Level
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. Also applies to data I/O (A and B: 8-15) and # 2 control pins.
1
DIR
X
X
X
H
H
H
H
L
L
L
L
1
CPAB
H or L
H or L
N
N
N
X
X
X
X
X
X
1
Inputs
N = LOW-to-HIGH Transition.
X = Immaterial
CPBA
H or L
H or L
N
X
X
X
X
X
X
N
N
1
SAB
H
H
X
X
X
X
X
X
X
L
L
1
SBA
X
X
X
X
X
X
X
H
H
L
L
1
Output
Data I/O (Note 1)
Input
Input
A
0–7
3
Output
Input
Input
B
0–7
Isolation
Clock An Data into A Register
Clock Bn Data Into B Register
An to Bn — Real Time (Transparent Mode)
Clock An Data to A Register
A Register to Bn (Stored Mode)
Clock An Data into A Register and Output to Bn
Bn to An — Real Time (Transparent Mode)
Clock Bn Data into B Register
B Register to An (Stored Mode)
Clock Bn into B Register and Output to An
Output Operation Mode
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