Homework SourseIn the Figure below a 680068230based microcomputer is requir
In the Figure below, a 6800/68230-based microcomputer is required to implement a voltmeter to measure voltage in the range 0 to 5 V and display the result in two decimal digits: one integer part and one fractional part. The microcomputer is required to start the A/D converter at the falling edge of a pulse via bit 0 of Port C. When the conversion is completed, the A/D\'s \"conversion complete\" signal will go HIGH. During the conversion, the A/D\'s \"conversion complete\" signal stays LOW. (a) using programmed I/O, the microcomputer is required to poll the A/D\'s \"conversion complete\" signal. When the conversion is completed, the microcomputer will input the 8-bit output from A/D via port B and display the voltage (0 to 5 V) in two decimal digits (one integer and one fractional) via port A on two TIL 311 displays. Note that the TIL 311 has an on-chip BCD to seven-segment decoder. The microcomputer will output each decimal digit on the common lines (bits 0-3 of port A) connected to the DCBA inputs of the displays. Each display will be enabled by outputting LOW on each LATCH line in sequence (one after another) so that the input voltage V_1(0 to 5 V) will be displayed with one integer part and fractional part. Write a 68000 assembly language program to accomplish this. Using interrupt I/O, repeat the task. Write the main program to configure the 68230 ports and starts the A/D. The service routine will input the A/D data, display the result, and stop. Write 68000 assembly language programs for the main and the service routine.
Solution
8500
3E 80
MVI A, 80H
8502
D3 0F
OUT CNTRL
8504
START:
8504
3E 00
MVI A, 00H
8506
D3 0D
OUT PORTB
8508
CD 15 85
CALL DELAY
850B
3E FF
MVI A, FFH
850D
D3 0D
OUT PORTB
850F
CD 15 85
CALL DELAY
8512
C3 04 85
JMP START
8515
DELAY:
8515
06 05
MVI B, 05
8517
0E FF
L1: MVI C, FFH
8519
0D
L2: DCR C
851A
C2 19 85
JNZ L2
851D
05
DCR B
8520
C2 17 85
JNZ L1
8521
C9
RET
