The 8051 Microcontroller and Embedded

Department of Computer Scien

ce and Information Engineering

National Cheng Kung University, TAIWAN

8255 HANEL
INTERFACING

ADC

Connection To The 8255

(cont

’)

Figure 15-11. 8255 Connection to ADC804

10k 150 pF

8255

ADC804

RESET

DecodingCircuitry

A2 A7

WRRD

From 8051

10kPOT

D0 D7 A0 CS

PA0 PA7

WRRD

PC0

A1

CS

RDWR D0 D7 INTR

VCCCLK RCLK INVin(+)Vin(-) A GNDVerf/2 GND