Hi Srinivas,

You have mentioned following code:
MOV DPTR,#1234h (16bit address)
MOVX @DPTR,#01h (data into that location)

As Eric said rightly ,how can u use the second line of above instruction?

It should be written as follows:

MOV A,#01H
MOV DPTR,#1234H
MOVX @DPTR,A

CAN U CONFIRM?

REGARDS,
Venkatesh