Bubble Sort in TASM

[kornicameister]

recently I've started to learning assembler (using TASM syntax), my first task was to made bubble sort...
I made an implementation, I checked it in Turbo Debugger and elements are in fact replaced if the appropriate condition is met, elements are swapped

but the program runs into infinite loop and I can not notice why is that
here is the entire code

;program do metody babelkowej
 
.MODEL SMALL
; Algorytm sortowania babelkowego:
; 1. Start.
; 2. index = 0; zamiany = 0;
; 3. Odczytaj dwa sasiadujace elementy z tablicy o pozycjach index oraz
;    index + 1; jezeli pierwszy z odczytanych elementow jest wiekszy od
;    swojego nastepnika, to zamien elementy miejscami oraz zwieksz zamiany.
; 4. Zwieksz index o jeden.
; 5. Jezeli index < dlugosc_tablicy - 2 to skacz do 3.
; 6. Skacz do 2 jezeli zamiany rozne od zera.
; 7. Stop.
.DATA
 
	t DB 01h, 02h, 00h, 10h, 12h, 33h, 15h, 09h, 11h, 08h, 0Ah, 00h 
		; 1,   2,   0,  16,  18,  51,  21,   9,  17,   8,  10,   0 ;po sorcie2=>	00h,00h,01h,02h,08h,09h,0Ah,10h,11h,12h,15h,33h
	t_size	EQU 	11 			; t_lenght
	again_s	db 		0		; if again_s == 1, swap was made, again
.CODE
s:
	mov ax,@DATA
	mov ds,ax 
	;buble sort
prepare:
	mov bx, OFFSET t 		; load the t offset into bx
again:
	mov again_s,0			; XOR the flag
	xor si,si				; XOR used indexing register 
nextElement:
	mov ax,[bx+si]			; first compared element
	mov cx,[bx+si+1]                 ; second one
	cmp ax,cx				; comparing
	jbe	noSwap			; if first <= next jmp no swap
	xchg ax,cx				; else swap
	mov again_s,1			; set the flag		
noSwap:
	inc si					; increment index
	cmp si,t_size			; compare the index with t_size
	jb	nextElement		
	cmp again_s,1                     ; if last element, check the flag
	je	again
koniec:
	mov ax,4c00h
	int 21h
.STACK 100H
end s

;program do metody babelkowej

.MODEL SMALL
; Algorytm sortowania babelkowego:
; 1. Start.
; 2. index = 0; zamiany = 0;
; 3. Odczytaj dwa sasiadujace elementy z tablicy o pozycjach index oraz
;    index + 1; jezeli pierwszy z odczytanych elementow jest wiekszy od
;    swojego nastepnika, to zamien elementy miejscami oraz zwieksz zamiany.
; 4. Zwieksz index o jeden.
; 5. Jezeli index < dlugosc_tablicy - 2 to skacz do 3.
; 6. Skacz do 2 jezeli zamiany rozne od zera.
; 7. Stop.
.DATA

	t DB 01h, 02h, 00h, 10h, 12h, 33h, 15h, 09h, 11h, 08h, 0Ah, 00h 
		; 1,   2,   0,  16,  18,  51,  21,   9,  17,   8,  10,   0 ;po sorcie2=>	00h,00h,01h,02h,08h,09h,0Ah,10h,11h,12h,15h,33h
	t_size	EQU 	11 			; t_lenght
	again_s	db 		0		; if again_s == 1, swap was made, again
.CODE
s:
	mov ax,@DATA
	mov ds,ax 
	;buble sort
prepare:
	mov bx, OFFSET t 		; load the t offset into bx
again:
	mov again_s,0			; XOR the flag
	xor si,si				; XOR used indexing register 
nextElement:
	mov ax,[bx+si]			; first compared element
	mov cx,[bx+si+1]                 ; second one
	cmp ax,cx				; comparing
	jbe	noSwap			; if first <= next jmp no swap
	xchg ax,cx				; else swap
	mov again_s,1			; set the flag		
noSwap:
	inc si					; increment index
	cmp si,t_size			; compare the index with t_size
	jb	nextElement		
	cmp again_s,1                     ; if last element, check the flag
	je	again
koniec:
	mov ax,4c00h
	int 21h
.STACK 100H
end s

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an important attention : I set t_size equal to 11, even though the real size equals 12. I made is so, because I tried to meet the condition when the index points at the last element (counting from 0)