Adding floating point numbers in assembly (yasm 8086)

Question

I have to write a program that would filter text lines from the input file. Each line is divided into six columns. Columns are separated from each other by a semicolon.

I implemented 3 filters:

1. Second column has to contain no u or v letters.
2. Third column has to contain a number so that it's sum of digits is equal to 7.
3. Last column has to contain number that belongs to the intervar of [2.34, 4.50]

Here's input file example:

B11;one;16;0;55;2.44
C1;two;8;0;17;3.77

First line would pass all of three filters.

My program works correctly with all of the filters. However, I have an additional task to find the sum of last columns floating point numbers but only on filtered lines.

I am not sure what would be the proper way to do it.

Here I have implemented filter function for the last column. Somehow from here I should put the filtered last column numbers into buffer and add all of them together. Here in this function I go through each character in the line.

procBelongsToInterval
    push ax
    xor ax, ax
.first:
    mov al, [di]

    inc di
    cmp al, '-'
    je  .break
    cmp al, '2'
    je  .firstBound
    cmp al, '3'
    je  .belongs
    cmp al, '4'
    je  .secondBound
    jmp .break

.firstBound:
    mov al, [di]
    inc di
    cmp al, '.'
    je  .firstBound
    cmp al, '3'
    jb  .break
    ja  .belongs
    mov al, [di]
    cmp al, '4'
    jae .belongs
    jb  .break

.secondBound:
    mov al, [di]
    inc di
    cmp al, '.'
    je  .secondBound
    cmp al, '5'
    ja  .break
    jb  .belongs
    mov al, [di]
    cmp al, '0'
    je  .belongs
    ja  .break

.belongs:
    mov [numberBelongsToInterval], byte 1
    jmp .end

.break:
    mov [numberBelongsToInterval], byte 0
    jmp .end

.end:
    pop ax
    ret