Aduc812 – Analog Devices ADuC812 User Manual
Page 49
REV. B
ADuC812
–49–
12 MHz
Variable Clock
Parameter
Min
Max
Min
Max
Unit
Figure
EXTERNAL DATA MEMORY WRITE CYCLE
t
WLWH
WR Pulsewidth
400
6t
CK
– 100
ns
54
t
AVLL
Address Valid after ALE Low
43
t
CK
– 40
ns
54
t
LLAX
Address Hold after ALE Low
48
t
CK
– 35
ns
54
t
LLWL
ALE Low to
RD or WR Low
200
300
3t
CK
– 50
3t
CK
+ 50
ns
54
t
AVWL
Address Valid to
RD or WR Low
203
4t
CK
– 130
ns
54
t
QVWX
Data Valid to
WR Transition
33
t
CK
– 50
ns
54
t
QVWH
Data Setup Before
WR
433
7t
CK
– 150
ns
54
t
WHQX
Data and Address Hold after
WR
33
t
CK
– 50
ns
54
t
WHLH
RD or WR High to ALE High
43
123
t
CK
– 40
6t
CK
– 100
ns
54
MCLK
ALE (O)
PSEN (O)
WR (O)
PORT 2 (O)
t
WHLH
t
WLWH
t
LLWL
t
AVWL
t
LLAX
t
AVLL
t
QVWX
t
QVWH
t
WHQX
A0–A7
DATA
A16–A23
A8–A15
Figure 53. External Data Memory Write Cycle