
PSD3XX Famly
45
Figure 21.  Timng of 8-Bit Multiplexed Address/Data Bus Using RD WR  (PSD3X2/3X3)
18
DATA VALID
CSI/A19
as CSI
DATA
IN
8
12
1
7
15
32
32
14
14
6
6
10
9 
ADDRESS A
2
ADDRESS B
3
4
13
32
5
2
16
17
12A
19
13
20
23
23
ADDRESS A
ADDRESS B
INPUT
INPUT
OUTPUT
OUTPUT
READ CYCLE
WRITE CYCLE
STABLE INPUT
STABLE INPUT
Direct 
(1)
PAD Input      
Multiplexed 
(2)
Inputs      
A0/AD0-
A7/AD7
Active Low
ALE
Active High
ALE
RD/E/DS as RD
BHE/PSEN
as PSEN
WR/V
PP
 or
RW as WR
Any of
PA0-PA7
as I/O Pin
Any of
PA0-PA7 Pins
as Address
Outputs
Any of
PB0-PB7
as I/O Pin
1
3
11
36
See referenced notes on page 64