First attempt to do bubble sort in 8086 assembly

scratch_10.asm

; Smallest number in an array of data

; Elements are stored from 0xf00 going forward so we ideally start there

; The layout is as follows
;            ┌──────────┬────────────────────────────┐
;            │          │                            │
;            │length    │items                       │
;            │          │                            │
;            └──────────┴────────────────────────────┘
;
;The length is the first memory location, i.e where register pair LH points to
; currently thats 00f0H(Hexadecimal) bec

; 1.) Load the address of the first element of the array into HL Pair

lxi h,00f0H 	;Point HL to the memory address at 4200H

; 2.) Move the count to C-reg
mov c,m
step3:nop
; 3. ) Copy it in D -register(For bubble sort (N-1) times required)
mov d,c

; 4.) Get the first value in A register
inr l; Increment L to point to the first element
mov a, m	; Move the first element to A

; 5.) Compare with the value at the next location
step5:nop
inr l
cmp m

; 6.) If they are out of order, exhange contents of A register and memory.

; So we are checking for ascending order. if we do the compare and A is less than memory
; the carry flag is set, if the carry flag is set it means they are in order
; so we don't need to swap, but if the flag is set we exhcange and continue

jc next;
; Here exchange contents of register with memory
mov b,m ; move memory to b(
mov m,a ; Move a to memory
mov a,b ; Move element that was in memory which we stored to b to a
dcr l	;	Reduce L
mov m,b ; Exchange elements in memory. this essentially does a swap
inr l 	; Increment L

next:nop
; 7.) Decrement D register by 1
dcr d
; 8.) Repeat step 5 and 7 till the value in D becomes zero
jnz step5
; 9.) Decrement C content by 1.
dcr c
; 10.) Repeat steps 3 to 9 till the value in C register becomes zero.
jnz step3

hlt