adns2610 problems

http://www.martijnthe.nl/2009/07/interfacing-an-optical-mouse-sensor-to-your-arduino/ ive been following these instructions, however in serial port i get only x=255 y=255 values regardless whether or not i move it.

note: i ve soldered every component on a separat board myself. do you think the heat could've damaged the adns chip? I ve already replaced it once. before it was returning values that continiously lowered one by one infinitely.

what do you think the problem is?

I think you need to collect more information - without a logic analyzer or oscilloscope you can stlil check that each signal is high or low as expected with idle, that the chip is getting full supply voltage, is drawing a reasonable supply current, etc.

A quality photo of your soldering could be useful - also a schematic. Do you have decoupling? You always need decoupling.