This requires "topping and tailing" according to the assembler you are using. Note that the mnemonics differ from assembler to assembler and from processor to processor.
Otherwise, I think this is good.
...
Mov ah, 02 [to output a character via int 21
mov dl, 0 [zero dl
loop1:
Cmp dl, n [when n is the number you specify
jl loop [jump to loop if less than n
add dl, 2
loop:
Int 21 [now acually do the outputting
jmp loop1
int 20 [halt
Note that blurtit will capitalise some of the mnemonics - please ignore this - items after the [are comments
Otherwise, I think this is good.
...
Mov ah, 02 [to output a character via int 21
mov dl, 0 [zero dl
loop1:
Cmp dl, n [when n is the number you specify
jl loop [jump to loop if less than n
add dl, 2
loop:
Int 21 [now acually do the outputting
jmp loop1
int 20 [halt
Note that blurtit will capitalise some of the mnemonics - please ignore this - items after the [are comments