Intel MCS48 User Manual page 178

M8048/M8748/M8035
WAVEFORMS
Instruction
Fetch
From
External
Program
Memory
!—
—
•CY
1 1
—
*AFC
p
,
CC "• tCA
h
'la
-*|«AL
1
*"
\
•dr \~
FLOATING >T
1
s
t FLOATING
>i
V
FLOATING
V
INSTRUCTION
Write to External Data
Memory
ALE
L
v-
*CC
*
'CA
'
"wo
BUS
FLOATINgYadDRESsYflOATINgY
DATA
Y
FLOATING
Read From
External Data
Memory
J
1
<CA
|—
BUS
FLOATING
y^rx
^y
Input
and Output
Waveforms
for
A.C.
Tests
TEST POINTS
A.C.
CHARACTERISTICS
Ta
=
-55°
C
to
(100°C 8748/8035/1 25°
C
8048/8035L),
Vcc = Vdd = +5V ±
10%, Vss
=
0V
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
tec
Control
Pulse
Width (PSEN, RD,
WR)
400 600
ns
tow
Data Setup before
WR
420 600
ns
twD Data
Hold After
WR
80 120
ns
C
L
= 20pF
tCY
Cycle
Time
2.5
15.0 4.17 15.0
Ms
(3.6
MHz
XTAL
8748/8035)
tDR
Data Hold 200
200
ns
tRD
PSEN,
RDto
Data
In
400
600
ns
*AW
Address Setup
to
WR
230 260
ns
tAD
Address Setup
to
Data
In
600
900
ns
tAFC
Address
Float to
RD,
PSEN
-40
-60
ns
tCA
Control Pulse to
ALE
10
10
ns
Note
1:
Control outputs:
C
L
=
80
pF
tQY =
2.5/iS for
8048/8035L
BUS
Outputs:
c
l
=150pF
4. 17/us for
8748/8035
6-26