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External data memory write cycle, External clock drive waveforms, External clock drive – Rainbow Electronics AT89LS51 User Manual

Page 23: At89ls51

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23

AT89LS51

3053A–8051–05/02

External Data Memory Write Cycle

External Clock Drive Waveforms

t

LHLL

t

LLWL

t

LLAX

t

WHLH

t

AVLL

t

WLWH

t

AVWL

t

QVWX

t

QVWH

t

WHQX

A0 - A7 FROM RI OR DPL

ALE

PSEN

WR

PORT 0

PORT 2

P2.0 - P2.7 OR A8 - A15 FROM DPH

A0 - A7 FROM PCL

A8 - A15 FROM PCH

DATA OUT

INSTR IN

t

CHCX

t

CHCX

t

CLCX

t

CLCL

t

CHCL

t

CLCH

V - 0.5V

CC

0.45V

0.2 V

- 0.1V

CC

0.7 V

CC

External Clock Drive

Symbol

Parameter

Min

Max

Units

1/t

CLCL

Oscillator Frequency

0

16

MHz

t

CLCL

Clock Period

62.5

ns

t

CHCX

High Time

20

ns

t

CLCX

Low Time

20

ns

t

CLCH

Rise Time

20

ns

t

CHCL

Fall Time

20

ns