User Manual

Functional Description (Continued)

TL/H/5671–20

Note 1: *Pin numbers for the DP8228 system controller, others are INS8080A.

Note 2: Pin 23 of the INS8228 must be tied to

12V througha1kXresistor to generate the RST 7

instruction when an interrupt is acknowledged as required by the accompanying sample program.

FIGURE 10. ADC0801– INS8080A CPU Interface

SAMPLE PROGRAM FOR

FIGURE 10

ADC0801– INS8080A CPU INTERFACE

0038 C3 00 03 RST 7: JMP LD DATA

## #

0100 21 00 02 START: LXI H 0200H ; HL pair will point to

; data storage locations

0103 31 00 04 RETURN: LXI SP 0400H ; Initialize stack pointer (Note 1)

0106 7D MOV A, L ; Test # of bytes entered

0107 FE OF CPI OF H ; If #416. JMP to

0109 CA 13 01 JZ CONT ; user program

010C D3 E0 OUT E0 H ; Start A/D

010E FB EI ; Enable interrupt

010F 00 LOOP: NOP ; Loop until end of

0110 C3 OF 01 JMP LOOP ; conversion

0113

CONT:

### #

(User program to

process data)

### #

0300 DB E0 LD DATA: IN E0 H ; Load data into accumulator

0302 77 MOV M, A ; Store data

0303 23 INX H ; Increment storage pointer

0304 C3 03 01 JMP RETURN

Note 1: The stack pointer must be dimensioned because a RST 7 instruction pushes the PC onto the stack.

Note 2: All address used were arbitrarily chosen.