Question

**Add comments to ARM code to explain steps**

Write an ARM assembly program to convert temperatures from Celsius to Fahrenheit or from Fahrenheit to Celsius. Here are the two formulas for your reference. Use variable to read and store values.

C= 5* (F - 32) / 9

F = (9 * C / 5 ) + 32

TempConvert.s

LDR R8,=temperature

LDR R1,[R8]

LDR R8,=unit

LDRB R2,[R8]

LDR R8,=celsius

LDRB R3,[R8]

LDR R8,=fahrenheit

LDRB R4,[R8]

MOV R6,#9

MOV R7,#5

;----C = 5 * (F - 32) / 9

SUB R5,R1,#32

MUL R5,R5,R7

UDIV R5,R5,R6

;------F = (9 * C / 5) + 32

MUL R5,R1,R6

UDIV R5,R5,R7

ADD R5,R5,#32

stop B stop

temperature DCD 50

unit DCB "F",0

celsius DCB "C",0

fahrenheit DCB "F",0

END

Answer 1

Assembly program to convert temperatures from Celsius to Fahrenheit.

DATA SEGMENT
T    DB ?
RES  DB 10 DUP ('$')
MSG1 DB "ENTER TEMPERATURE IN CELSIUS (ONLY IN 2 DIGITS) : $"
MSG2 DB 10,13,"CONVERTED IS FAHRENHEIT (TEMPERATURE) : $"
DATA ENDS
CODE SEGMENT
ASSUME DS:DATA,CS:CODE

;START is the label used to show the starting point of the code which is written in the Code Segment.
START:
MOV AX,DATA
MOV DS,AX         ;move contents of AX into DS
LEA DX,MSG1
MOV AH,9         ;move 9 into AH
INT 21H
MOV AH,1
INT 21H
SUB AL,30H
MOV AH,0
MOV BL,10
MUL BL
MOV BL,AL
MOV AH,1
INT 21H
SUB AL,30H
MOV AH,0
ADD AL,BL
MOV T,AL
MOV DL,9
MUL DL
MOV BL,5
DIV BL
MOV AH,0
ADD AL,32
LEA SI,RES
CALL HEX2DEC
LEA DX,MSG2
MOV AH,9
INT 21H
LEA DX,RES
MOV AH,9
INT 21H
MOV AH,4CH
INT 21H
CODE ENDS
HEX2DEC PROC NEAR
MOV CX,0
MOV BX,10
LOOP1: MOV DX,0
DIV BX
ADD DL,30H
PUSH DX
INC CX
CMP AX,9
JG LOOP1
ADD AL,30H
MOV [SI],AL
LOOP2: POP AX
INC SI
MOV [SI],AL
LOOP LOOP2
RET
HEX2DEC ENDP
END START