Rainbow Electronics ADC0848 - Manual (Page 15)

Applications Information
(Continued)
ADC0844 INS8039 Interface
TL H 5016 – 27
SAMPLE PROGRAM FOR ADC0844 INS8039 INTERFACE
CONVERTING TWO RATIOMETRIC DIFFERENTIAL SIGNALS
ORG 0H
0000 04 10 JMP BEGIN START PROGRAM AT ADDR 10
ORG 10H MAIN PROGRAM
0010 B9 FF BEGIN MOV R1 0FFH LOAD R1 WITH A UNUSED ADDR
LOCATION
0012 B8 20 MOV R0 20H A D DATA ADDRESS
0014 89 FF ORL P1 0FFH SET PORT 1 OUTPUTS HIGH
0016 23 00 MOV A 00H LOAD THE ACC WITH A D MUX DATA
CH1 AND CH2 DIFFERENTIAL
0018 14 50 CALL CONV CALL THE CONVERSION SUBROUTINE
001A 23 02 MOV A 02H LOAD THE ACC WITH A D MUX DATA
CH3 AND CH4 DIFFERENTIAL
001C 18 INC R0 INCREMENT THE A D DATA ADDRESS
001D 14 50 CALL CONV CALL THE CONVERSION SUBROUTINE
CONTINUE MAIN PROGRAM
CONVERSION SUBROUTINE
ENTRY ACC
A D MUX DATA
EXIT ACC CONVERTED DATA
ORG 50H
0050 99 FE CONV ANL P1 0FEH CHIP SELECT THE A D
0052 91 MOVX R1 A LOAD A D MUX START CONVERSION
0053 09 LOOP IN A P1 INPUT INTR STATE
0054 32 53 JB1 LOOP IF INTR e 1 GOTO LOOP
0056 81 MOVX A R1 IF INTR e 0 INPUT A D DATA
0057 89 01 ORL P1 01H CLEAR THE A D CHIP SELECT
0059 A0 MOV R0 A STORE THE A D DATA
005A 83 RET RETURN TO MAIN PROGRAM
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