mov r0, #HIGH ms 
00001$: mov r1, #LOW ms 
00002$: nop 

        nop 
        djnz r1, 00002$ 
        djnz r0, 00001$ 
        ret

Your delay routine will not function well. What if LOW ms is a small number: 1, 2 ... ? You reload R1 with it, so the delay is equally dependent on lower byte as on higher ! The exact routine should look like this:

	MOV	R0,#HIGH
	INC	R0		; In case of HIGH=0, R0 must be 1
;                               to go out from the loop immediately !
	MOV	R1,#LOW
	INC	R1		; Same as up

DLY:	NOP

	DJNZ	R1,DLY
	DJNZ	R0,DLY

This way, the DLY loop will be performed (LOW + HIGH * 256) times. Exactly what we need.

Regards, Slobodan