Aduc812 – Analog Devices ADuC812 User Manual
Page 48
REV. B
ADuC812
–48–
12 MHz
Variable Clock
Parameter
Min
Max
Min
Max
Unit
Figure
EXTERNAL DATA MEMORY READ CYCLE
t
RLRH
RD Pulsewidth
400
6t
CK
– 100
ns
53
t
AVLL
Address Valid after ALE Low
43
t
CK
– 40
ns
53
t
LLAX
Address Hold after ALE Low
48
t
CK
– 35
ns
53
t
RLDV
RD Low to Valid Data In
252
5t
CK
– 165
ns
53
t
RHDX
Data and Address Hold after
RD
0
0
ns
53
t
RHDZ
Data Float after
RD
97
2t
CK
–70
ns
53
t
LLDV
ALE Low to Valid Data In
517
8t
CK
– 150
ns
53
t
AVDV
Address to Valid Data In
585
9t
CK
– 165
ns
53
t
LLWL
ALE Low to
RD or WR Low
200
300
3t
CK
– 50
3t
CK
+ 50
ns
53
t
AVWL
Address Valid to
RD or WR Low
203
4t
CK
– 130
ns
53
t
RLAZ
RD Low to Address Float
0
0
ns
53
t
WHLH
RD or WR High to ALE High
43
123
t
CK
– 40
6t
CK
– 100
ns
53
MCLK
ALE (O)
PSEN (O)
RD (O)
PORT 0 (I/O)
PORT 2 (O)
t
WHLH
t
LLDV
t
LLWL
t
RLRH
t
AVWL
t
LLAX
t
AVLL
t
RLAZ
t
RHDX
t
RHDZ
t
AVDV
A0–A7 (OUT)
DATA (IN)
A16–A23
A8–A15
t
RLDV
Figure 52. External Data Memory Read Cycle