Assembly Code

I am trying to write 0xAA to Address location 0x5555.
The following code is working. May someone kindly explain in details how C167 controller interpret it? Why is #09555H used???

MOV	DPP2,#0001H
MOV	R12,#09555H
MOVB	RL1,#00AAH
MOV	[R12],RL1

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