Сложение, вычитание и умножение 32-разрядных чисел в формате с плавающей точкой (float)

cseg at 0
 
jmp start
 
main segment code
 
_data segment data
 
rseg _data
 
first: ds 4
 
second: ds 4
 
result: ds 8
 
stack: ds 2
 
rseg main
 
_add:
 
mov a, r6
 
add a, r7
 
mov r7, a
 
mov a, r5
 
addc a, r6 // 2 + 2 + C
 
mov r6, a //R6 - 2
 
mov a, r4
 
addc a, r5 // 3 + 3 + C
 
clr a
 
mov r4, a
 
mov r5, a
 
mov r6, a
 
addc a, #0
 
mov r3, a
 
ret
 
_sub:
 
mov a, r4
 
subb a, r7
 
mov r7, a
 
mov a, r5
 
subb a, r6
 
mov r6, a
 
mov a, r6
 
subb a, r5
 
mov r5, a
 
clr a
 
mov r4, a
 
mov r5, a
 
mov r6, a
 
ret
 
_mul:
 
//zapolnenie
 
mov first, r4
 
mov first+1, r5
 
mov first+2, r6
 
mov first+3, r7
 
mov second, r4
 
mov second+1, r5
 
mov second+2, r6
 
mov second+3, r7
 
razrFirst equ r4
 
razrSecond equ r5
 
razrResult equ r4
 
mov razrFirst, #3 //counter for first
 
mov razrSecond, #3 //counter for second
 
_mult:
 
//adress of res
 
mov a, razrFirst
 
add a, razrSecond
 
inc a //sum razr +1
 
add a, #result
 
mov razrResult, a
 
//bytes of numbers
 
mov a, #second
 
add a, razrSecond
 
mov r4, a
 
mov a, @r4
 
mov b, a
 
mov a, #first
 
add a, razrFirst
 
mov r4, a
 
mov a, @r4
 
mul ab
 
//res a
 
mov r4, a
 
mov a, @razrResult
 
add a, r4
 
mov @razrResult, a
 
//res b
 
dec razrResult
 
mov r4, b
 
mov a, @razrResult
 
addc a, r4
 
mov @razrResult, a
 
check:
 
jc cycle
 
jmp next
 
//ress c
 
cycle:
 
dec razrResult
 
mov a, @razrResult
 
addc a, #0
 
mov @razrResult, a
 
jmp check
 
next:
 
//change registers
 
mov a, razrFirst
 
dec a
 
mov razrFirst, a
 
cjne razrFirst, #-1, _mult
 
change:
 
mov razrFirst, #3
 
mov a, razrSecond
 
dec a
 
mov razrSecond, a
 
cjne razrSecond, #-1, _mult
 
mov r4, first
 
mov r5, first+1
 
mov r6, first+2
 
mov r7, first+3
 
mov r4, second
 
mov r5, second+1
 
mov r6, second+2
 
mov r7, second+3
 
ret
 
start:
 
mov r4, #1 //4 RAZR
 
mov r5, #2 //3 RAZR
 
mov r6, #3 //2 RAZR
 
mov r7, #4 //1 RAZR
 
mov r4, #5 //4
 
mov r5, #6 //3
 
mov r6, #7 //2
 
mov r7, #8 //1
 
//acall _add
 
//acall _sub
 
acall _mul
 
jmp $
 
end