MOTOROLA
A-20
ELECTRICAL CHARACTERISTICS
MC68HC11A8
TECHNICAL DATA
A
NOTES:
1.Formula only for dc to 2 MHz.
2.Input clocks with duty cycles other than 50% affect bus performance. Timing parameters affected by input clock
duty cycle are identified by (a) and (b). To recalculate the approximate bus timing values, substitute the following
expressions in place of 1/8 t
cyc
in the above formulas, where applicable:
(a) (1-DC) x 1/4 t
cyc
(b) DC x 1/4 t
cyc
Where:
DC is the decimal value of duty cycle percentage (high time).
3.All timing is shown with respect to 20% V
DD
and 70% V
DD
, unless otherwise noted.
Table A-7a Expansion Bus Timing (MC68L11A8)
V
DD
= 3.0 Vdc to 5.5 Vdc, V
SS
= 0 Vdc, T
A
= T
L
to T
H
Characteristic
Num
Symbol
1.0 MHz
Min
dc
1000
475
2.0 MHz
Min
dc
500
225
Unit
Max
1.0
—
—
Max
2.0
—
—
Frequency of Operation (E-Clock Frequency)
Cycle Time
Pulse Width, E Low
PW
EL
= 1/2 t
cyc
– 23 ns
Pulse Width, E High
PW
EH
= 1/2 t
cyc
– 28 ns
4a, b E and AS Rise and Fall Time
f
o
MHz
ns
ns
1
2
t
cyc
PW
EL
(Note 1)
3
(Note 1)
PW
EH
470
—
220
—
ns
t
r
t
f
—
25
25
—
—
25
25
—
ns
9
Address Hold Time
t
AH
= 1/8 t
cyc
– 29.5 ns
Non-Muxed Address Valid Time to E Rise
t
AV
= PW
EL
– (t
ASD
+ 80 ns)
Read Data Setup Time
Read Data Hold Time (Max = t
MAD
)
Write Data Delay Time
t
DDW
= 1/8 t
cyc
+ 65.5 ns
Write Data Hold Time
t
DHW
= 1/8 t
cyc
– 29.5 ns
Muxed Address Valid Time to E Rise
t
AVM
= PW
EL
– (t
ASD
+ 90 ns)
Muxed Address Valid Time to AS Fall
t
ASL
= PW
ASH
– 70 ns
Muxed Address Hold Time
t
AHL
= 1/8 t
cyc
– 29.5 ns
Delay Time, E to AS Rise
t
ASD
= 1/8 t
cyc
– 9.5 ns
Pulse Width, AS High
PW
ASH
= 1/4 t
cyc
– 29 ns
Delay Time, AS to E Rise
t
ASED
= 1/8 t
cyc
– 9.5 ns
MPU Address Access Time
t
ACCA
= t
cyc
– (PW
EL
– t
AVM
) – t
DSR
– t
f
MPU Access Time
t
ACCE
= PW
EH
– t
DSR
Muxed Address Delay
(Previous Cycle MPU Read)
t
MAD
= t
ASD
+ 30 ns
(Note 1, 2a)
t
AH
95
33
ns
12
(Note 1, 2a)
t
AV
275
—
88
—
ns
17
18
19
t
DSR
t
DHR
t
DDW
30
0
—
—
150
195
30
0
—
—
88
133
ns
ns
ns
(Note 1, 2a)
21
(Note 1, 2a)
t
DHW
95
—
33
—
ns
22
(Note 1, 2a)
t
AVM
265
—
78
—
ns
24
(Note 1)
t
ASL
150
—
25
—
ns
25
(Note 1, 2b)
t
AHL
95
—
33
—
ns
26
(Note 1, 2a)
t
ASD
120
—
58
—
ns
27
(Note 1)
PW
ASH
220
—
95
—
ns
28
(Note 1, 2b)
(Note 2a)
t
ASED
120
—
58
—
ns
29
t
ACCA
735
—
298
—
ns
35
t
ACCE
—
440
—
190
ns
36
(Note 1, 2a)
t
MAD
150
—
88
—
ns