SAMPLE PROGRAM FOR ADC0841 — NSC800 INTERFACE

0010

NCONV

EQU

16

;TWICE THE NUMBER OF REQUIRED

;CONVERSIONS

000F

DEL

EQU

15

;DELAY 60 µsec CONVERSION

001F

CS

EQU

1FH

;THE BOARD ADDRESS

3C00

ADDTA

EQU

003CH

;START OF RAM FOR A/D

;DATA

0000'

00

DTA:

DB

08H

;DATA

0001'

0E 1F

START:

LD

C,CS

0003'

06 16

LD

B,NCONV

0005'

21 0000'

LD

HL,DTA

0008'

11 003C

LD

DE,ADDTA

000B'

ED A3

STCONV:

OUTI

;START A CONVERSION

000D'

EB

EX

DE,HL

;HL=RAM ADDRESS FOR THE

;A/D DATA

000E'

3E 0F

LD

A,DEL

0010'

3D

WAIT:

DEC

A

;WAIT 60 µsec FOR THE

0011'

C2 0013'

JP

NZ,WAIT

;CONVERSION TO FINISH

0014'

ED A2

INI

;STORE THE A/D’S DATA

;THE REQUIRED CONVERSIONS

COMPLETED?

0016'

EB

EX

DE,HL

0017'

C2 000E'

JP

NZ,STCONV

;IF NOT GOTO STCONV

END

Note 12: A conversion is started, then a 60 µs wait for the A/D to complete a conversion and the data is stored at address ADDTA for the first conversion,

ADDTA + 1 for the second conversion, etc. for a total of 8 conversions.

DS008557-21

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12