Intel MCS48 User Manual page 166

ID8048/8748/8035L
WAVEFORMS
Instruction Fetch
From
External
Program
Memory
-. t
u
*
*CY
1
—
l AFC
*_
—
<cc
-
•CA
h
'la
-*JVl
—~
l DR
|-
FLOATING
Nt
/
F
oat
ING
V
IMG
Y
INSTRUCTION
Write to External Data
Memory
ALE
1_
h
'cc -\
'CA
h
bus floatingYaddressYfloating
Y
data
Y
floating
Read From
External Data
Memory
J
L
J
L
i-
BUS
FLOATING
FLOATING
/
<
x
>
(data^«
l-w-
D
-
Input
and Output Waveforms
for A.C.
Tests
:test points;
A.C.
CHARACTERISTICS
T
A
=-40°
Cto+85°C,
V
CC
= V
DD
= +5V
±10%
Vss
=
OV
Symbol
Parameter
8048/8035L
8748/8035
Unit
Conditions (Note
1)
Min. Max. Min. Max.
tLL
ALE
Pulse
Width
200
300 ns
tAL
Address Setup
to
ALE
120 120 ns
tLA
Address Hold from
ALE
80 80 ns
l
CC
Control Pulse
Width (PSEN, RD, WR)
400 600 ns
^DW
Data Setup Before
WR
420 600
ns
t\A/D
Data Hold
After
WR
80 120 ns
C
L
= 20pF
*CY
Cycle
Time
2.5 15.0
4.17
15.0
MS (3.6
MHz XTAL
8748/8035)
*DR
Data Hold
200
200 ns
*RD
PSEN, RD
to
Data
In
400 600 ns
*AW
Address Setup
to
WR
230 260 ns
Ud Address Setup
to
Data
In
600 900 ns
*afc
Address
Float to
RD,
PSEN
-40
-60
ns
t
C A
Control
Pulse
to
ALE
10 10 ns
Note
1:
Control Outputs: C\_= 80 pF
tcy
=
2.5
^s for
8048/8035L
BUS
Outputs: C|_= 150
pF
4.17 ps
for
8748/8035
6-14