74F646 Datasheet, PDF (6/16 Pages) NXP Semiconductors – Octal transceiver/register, non-inverting 3-State

Philips Semiconductors
Transceivers/registers
Product specification
74F646/A/74F648/A
The following examples demonstrate the four fundamental
bus–management functions that can be performed with the
74F646/646A and 74F648/648A. The select pins determine whether
BUS MANAGEMENT FUNCTIONS
REAL TIME BUS TRANSFER
BUS B TO BUS A
REAL TIME BUS TRANSFER
BUS A TO BUS B
data is stored or transferred through the device in real time. The
output enable pins determine the direction of the data flow.
STORAGE FROM
A, B, OR A AND B
TRANSFER STORED DATA
TO A AND/OR B
BUS A
BUS B
BUS A
BUS B
BUS A
BUS B
BUS A
BUS B
OE DIR CPAB CPBA SAB SBA
LL X X X L
OE DIR CPAB CPBA SAB SBA
LH X X L X
OE DIR
XX
XX
HX
CPAB CPBA SAB
↑XX
X↑X
↑↑X
SBA
X
X
X
OE DIR CPAB CPBA SAB SBA
L L X H or L X H
L H H or L X H X
SF00392
1990 Sep 25
6