hi,

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		CLR	A
IDATALOOP:	MOV	@R0,A; my code stuck in the loop
		DJNZ	R0,IDATALOOP;

Indeed, you load R0 with zero, then do DJNZ with R0 and then clear it again -- infinite loop.
Hint: I think you should use MOVX for xdata memory access.
Moreover, xdata memory size is more than 256 bytes so I think you should use DPTR and corresponded number of loops.

Regards,
Oleg