DS83C520 Maxim, DS83C520 Datasheet - Page 33

• Manufacturer Part Number: DS83C520
• Description: The DS87C520/DS83C520 EPROM/ROM high-speed microcontrollers are fast 8051-compatible microcontrollers
• Manufacturer: Maxim

MOVX CHARACTERISTICS
Note 1:
Note 2:
Data Access ALE Pulse Width
Port 0 Address Valid to ALE Low
Address Hold after ALE Low for
MOVX Write
RD Pulse Width
WR Pulse Width
RD Low to Valid Data In
Data Hold After Read
Data Float after Read
ALE Low to Valid Data In
Port 0 Address to Valid Data In
Port 2 Address to Valid Data In
ALE Low to RD or WR Low
Port 0 Address to RD or WR Low
Port 2 Address to RD or WR Low
Data Valid to WR Transition
Data Hold after Write
RD Low to Address Float
RD or WR High to ALE High
t
each Stretch selection.
Address is driven strongly until ALE falls, and is then held in a weak latch until overdriven externally.
PARAMETER
MCS
is a time period related to the Stretch memory cycle selection. The following table shows the value of t
SYMBOL
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
AVDV1
AVDV2
AVWL1
AVWL2
t
LHLL2
AVLL2
LLAX2
WLWH
QVWX
WHQX
WHLH
RHDX
LLWL
RLRH
RLDV
RHDZ
LLDV
RLAZ
DS87C520/DS83C520 EPROM/ROM High-Speed Microcontrollers
33 of 43
0.5t
0.5t
1.5t
2.5t
1.5t
0.5t
2t
2t
2t
2t
2t
t
t
t
t
t
t
t
t
VARIABLE CLOCK
MCS
MCS
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
MIN
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
-6
-4
0
-10
-10
-5
-7
-5
-9
-5
-5
-5
-5
-5
-7
-6
-10
-10
-17
-16
-5
-5
t
t
MCS
t
MCS
2.5t
3.5t
MCS
0.5t
2t
3t
(Note 2)
2t
t
t
t
t
MAX
MCS
+2.5t
CLCL
CLCL
CLCL
CLCL
+t
CLCL
CLCL
+2t
CLCL
CLCL
CLCL
29
37
10
CLCL
-24
+5
+5
CLCL
-22
-5
-29
-5
CLCL
-31
-37
+5
-26
-
-
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
STRETCH
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
MCS
—
—
—
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
=0
>0
for