AT89C51-12 ATMEL [ATMEL Corporation], AT89C51-12 Datasheet - Page 12

• Manufacturer Part Number: AT89C51-12
• Description: 8-Bit Microcontroller with 4K Bytes Flash
• Manufacturer: ATMEL [ATMEL Corporation]

External Data Memory Write Cycle
External Clock Drive Waveforms
External Clock Drive
4-40
Symbol
1/t
t
t
t
t
t
CLCL
CHCX
CLCX
CLCH
CHCL
CLCL
0.45V
PORT 0
PORT 2
V
PSEN
CC
ALE
WR
- 0.5V
Parameter
Oscillator Frequency
Clock Period
High Time
Low Time
Rise Time
Fall Time
0.2 V
A0 - A7 FROM RI OR DPL
0.7 V
CC
AT89C51
t
LHLL
t
AVLL
- 0.1V
CC
t
CHCX
P2.0 - P2.7 OR A8 - A15 FROM DPH
t
AVWL
t
LLAX
t
QVWX
t
LLWL
DATA OUT
t
QVWH
t
t
CLCX
WLWH
t
CLCH
41.6
Min
15
15
0
t
t
WHQX
CLCL
t
A0 - A7 FROM PCL
WHLH
A8 - A15 FROM PCH
t
CHCX
Max
24
20
20
INSTR IN
t
CHCL
Units
MHz
ns
ns
ns
ns
ns