DS80C320/DS80C323 High-Speed/Low-Power Microcontrollers

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EXTERNAL CLOCK CHARACTERISTICS

PARAMETER

SYMBOL

MIN

TYP

MAX

UNITS

Clock High Time

10

ns

Clock Low Time

10

ns

Clock Rise Time

5

ns

Clock Fall Time

5

ns

SERIAL PORT MODE 0 TIMING CHARACTERISTICS

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

SM2 = 0;

12 clocks per cycle

Serial Port Clock

Cycle Time

SM2 = 1;

4 clocks per cycle

ns

SM2 = 0

12 clocks per cycle

Output Data Setup to

Clock Rising Edge

SM2 = 1;

4 clocks per cycle

ns

SM2 = 0

12 clocks per cycle

Output Data Hold

from Clock Rising

SM2 = 1;

4 clocks per cycle

ns

SM2 = 0;

12 clocks per cycle

Input Data Hold After

Clock Rising

SM2 = 1;

4 clocks per cycle

ns

SM2 = 0;

12 clocks per cycle

Clock Rising Edge to

Input Data Valid

SM2 = 1

4 clocks per cycle

ns

EXPLANATION OF AC SYMBOLS

In an effort to remain compatible with the original 8051 family, this device specifies the same parameter as such

devices, using the same symbols. For completeness, the following is an explanation of the symbols.

t

Time

A

Address

C

Clock

D

Input data

H

Logic level high

L

Logic level low

I

Instruction

P

PSEN

Q

Output data

R

RD

signal

V

Valid

W

WR

signal

X

No longer a valid logic level

Z

Tri-state