18243

EXPANDER INTERFACE

":"

 

I/O

cs

 

 

P4

I/O

 

 

 

 

PROG

 

 

TEST

P5

I/O

8048

INPUTS

8243

 

 

 

 

 

P5

I/O

P20·P23

 

DATA IN

 

 

 

P2

I/O

 

 

P7

 

OUTPUT EXPANDER TIMING

 

PROG ~""_____..J/

BITS 3,2

BITS 1,0

OO} READ

OO}01

 

 

PORT

P20·P23 --<I..._--JX'-_____...I)>---

01

WRITE

10

OR

10

AODRESS

11_

ANO

"

 

 

 

 

ADDRESS (4·8ITSI DATA (4-BITSI

BUS

PORT 1

B04B

PORT 2

PROG~----------------

~------------------

~-----------------

4------------------

~

USING MULTIPLE 8243'5

6-68

AFN-OOBB1A-OS

Page 211
Image 211
Intel mcs-48 manual Output Expander Timing