; AVGTEMP.ASM
; Converts Fahrenheit Temp to Celsius

CPU "8086.tbl"
HOF "BIN16"

start: ORG 0100h

; START OF PROGRAM
    FARH: dfb 68
    CENT: dfb 00

main_program:
    mov ax,0000           ; Clear AX Register
    movb al,[FARH]        ; Move Fahrenheit Temp to AL Register
    subb al,20h           ; Subtract 20H from Fahrenheit Temp
    movb bl,05h           ; Move 05h to BL Register
    movb ah,00h           ; Clear AH register
    mulb bl               ; Multiply AL by 5
    movb bl,09h           ; Move 09h to BL register
    divb bl               ; Divide AL by 9
    movb [CENT],al        ; Move result to Centigrade (AL Register)
    mov  ax,4c00h         ; Return to DOS
    int 21h   
    ret
    end start