AT89C51ED2-SMRUM Datasheet, PDF (119/137 Pages) ATMEL Corporation – 8-bit Flash Microcontroller

AT89C51RD2/ED2
Table 25-3. AC Parameters for a Variable Clock
Symbol
T_LHLL
T_AVLL
T_LLAX
T_LLIV
T_LLPL
T_PLPH
T_PLIV
T_PXIX
T_PXIZ
T_AVIV
T_PLAZ
Type
Min
Min
Min
Max
Min
Min
Max
Min
Max
Max
Max
Standard Clock
2T-x
T-x
T-x
4T-x
T-x
3T-x
3T-x
x
T-x
5T-x
x
X2 Clock
T-x
0.5 T - x
0.5 T - x
2T-x
0.5 T - x
1.5 T - x
1.5 T - x
x
0.5 T - x
2.5 T - x
x
X parameter for
-M range
15
20
20
35
15
25
45
0
15
45
10
Units
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
25.3.3 External Program Memory Read Cycle
ALE
PSEN
PORT 0 INSTR IN
T_LHLL
T_LLAX
T_AVLL
A0-A7
T_LLIV
T_LLPL
T_PLPH
12 T_CLCL
T_PLIV
TPLAZ
T_PXIX
INSTR IN
T_PXAV
T_PXIZ
A0-A7
PORT 2
ADDRESS
OR SFR-P2
T_AVIV
ADDRESS A8-A15
INSTR IN
ADDRESS A8-A15
25.3.4 External Data Memory Characteristics
4235K–8051–05/08
119