The following program assembled with ASEM-51

var1	equ	1ch
var2	equ	0ffh
	org	30h
	mov	var1,var2
	mov	var2,var1
	END

The List file:

 Line  I  Addr  Code            Source

    1:		N      001C	var1	equ	1ch
    2:		N      00FF	var2	equ	0ffh
    3:		N      0030		org	30h
    4:	  0030	85 FF 1C		mov	var1,var2
    5:	  0033	85 1C FF		mov	var2,var1
    6:					END

Intel Hex File:

:0600300085FF1C851CFF8A
:00000001FF

Command Line Used: d52.exe test2 /D/U
No Control File (.ctl) used.
Output:

;
;  D52 V3.4.1 8052 Disassembly of test2.hex
;  2007/09/06 10:56
;
	ORG	30H
;
	MOV	RB3R4,T3	; 0030   85 ff 1c   ...
	MOV	T3,RB3R4	; 0033   85 1c ff   ...
;
;	Register/Memory Equates
;
RB3R4	EQU	1CH
;
	END
;

What's T3 ?

Jon