Datasheet

CY54FCT646T, CY74FCT646T
8-BIT REGISTERED TRANSCEIVERS
WITH 3-STATE OUTPUTS
SCCS031A – JULY 1994 – REVISED OCTOBER 2001
3
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
21
L
3
DIR
L
1
CPAB
X
23
CPBA
X
2
SAB
X
22
SBA
L
21
L
3
DIR
H
1
CPAB
X
23
CPBA
X
2
SAB
L
22
SBA
X
21
L
3
DIR
H
1
CPAB
23
CPBA
X
2
SAB
X
22
SBA
X
21
L
3
L
1
CPAB
X
23
CPBA
H or L
2
SAB
X
22
SBA
H
L
H
L
X
XX
X
X
X
L H H or L X H X
↑
↑
↑↑
BUS B
BUS A
BUS B
BUS A
BUS B
BUS A
BUS B
BUS A
G
GG
REAL-TIME TRANSFER
BUS B TO BUS A
REAL-TIME TRANSFER
BUS A TO BUS B
STORAGE FROM
A AND/OR B
TRANSFER STORED DATA
TO A AND/OR B
DIR
†
†
Cannot transfer data to A bus and B bus simultaneously.
G
Figure 1. Bus-Management Functions