8XC198

EXTERNAL CRYSTAL CONNECTIONS

272034 – 32

NOTE

Keep oscillator components close to chip and use

ceramic resonators consult manufacturer for recom-

mended capacitor values

EXTERNAL CLOCK CONNECTIONS

272034 – 33

NOTE

Required if open collector TTL driver used Not need-

ed if CMOS driver is used

AC TESTING INPUT OUTPUT WAVEFORMS

272034 – 26

AC Testing inputs are driven at 24V for a Logic ‘‘1’’ and 045V for

a Logic ‘‘0’’ Timing measurements are made at 20V for a Logic

‘‘1’’ and 08V for a Logic ‘‘0’’

FLOAT WAVEFORMS

272034 – 27

For Timing Purposes a Port Pin is no Longer Floating when a

200 mV change from Load Voltage Occurs and Begins to Float

EXPLANATION OF AC SYMBOLS

Each symbol is two pairs of letters prefixed by ‘‘T’’ for time The characters in a pair indicate a signal and its

condition respectively Symbols represent the time between the two signalcondition points

Conditions

H

- High

L

- Low

V

- Valid

X

- No Longer Valid

Z

- Floating

Signals

A

- Address

D

- DATA IN

L

- ALEADV

Q

- DATA OUT

R- RD

W- WR

X

- XTAL1

Y

- READY

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