AT89C55WD View Datasheet(PDF) - Atmel Corporation
Part Name
Description
MFG CO.
'AT89C55WD' PDF : 35 Pages View PDF
31. External Data Memory Write Cycle
ALE
tLHLL
PSEN
WR
PORT 0
PORT 2
tLLWL
tWLWH
tAVLL
tLLAX
tQVWX
A0 - A7 FROM RI OR DPL
tAVWL
tQVWH
DATA OUT
P2.0 - P2.7 OR A8 - A15 FROM DPH
AT89C55WD
tWHLH
tWHQX
A0 - A7 FROM PCL INSTR IN
A8 - A15 FROM PCH
32. External Clock Drive Waveforms
VCC - 0.5V
tCHCX
0.7 VCC
0.45V
0.2 VCC - 0.1V
tCLCH
tCLCX
tCHCX
tCLCL
tCHCL
33. External Clock Drive
Symbol
1/tCLCL
tCLCL
tCHCX
tCLCX
tCLCH
tCHCL
Parameter
Oscillator Frequency
Clock Period
High Time
Low Time
Rise Time
Fall Time
Min
Max
Units
0
33
MHz
30
ns
12
ns
12
ns
5
ns
5
ns
29
1921C–MICRO–3/05
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