8048/8035L/8748/8748-6/8748-8/8035/8035-8

WAVEFORMS

Instruction Fetch From External Program Memory

Read From External Data MemorY

I===i---h·1

ALE J IL--___~I---'LALE

RD

JL

1--'ee --I'eA I---

---- II .1

BUS

BUS

'm ~I I~FLOATlNG~1 i,'OR

~--FL-O-AT-'N-G--

 

1.'Ro-1

 

 

1- tAD --

 

Write to External Data Memory

Input and Output Waveforms for A.C. Tests

ALE J

L

 

WR

2 . 4 ---- "'"\ 2.2-...

 

 

..,2.2V

 

_ ____J)(O,S--TEST POINTS ........ O.sA

 

0.45

' -----

BUS

A.C. CHARACTERISTICS TA = O·Cto WC',Vee = VDD = + 5V ;: 10% ,Vss = OV

Symbol .1

Parameter

tLL

ALE Pulse Width

tAL

Address Setup to ALE

tLA

Address Hold from ALE

tcc

Control Pulse Width (PSEN, RO, WR)

tow

Data Setup before WR

two

Data Hold After WR

tCY

Cycle Time

 

8048

18748-8**

 

 

 

8748-6

 

 

 

8035·8

Unit I

Conditions (Note 1)

874818035/8035L

Min.

Max.

Min.

Max.

 

 

400

 

600

 

ns

 

120

 

150

 

ns

 

80

 

80

 

ns

 

700

 

1500

 

ns

 

500

 

640

 

ns

 

120

 

120

 

ns

CL =20pF

2.5

15,0

4.17

15.0

IJS

6 MHz XTAL=2.5

 

 

 

 

 

(3.6 MHz XTAL for - 8

tOR tRO tAW tAO tAFC tCA

Data Hold

 

U 200

0 200

ns

PSEN, RO to Data In

500

750

ns

Address Setup to WR

230

260

ns

Address Setup to Data In

950

1450

ns

Address Float to RD, PSEN

0

0

ns

Control Pulse to ALE

10

20

ns

Note t: Control outputs'

CL = SO pF

ICV = 2.5 ~s lor standard parts

*TA = O·Cto55-Cfor8748-8

BUS Outputs:

CL= tSO pF

=4.17 ~s lor-8 parts

uVCCand VOO for 8748-8 and 8035-6are ±5'1.

6-13

AFN'()I354A-05,

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Intel mcs-48 manual ===i---h·1