More to what Dave noted, my experience with Telecontroli was not the best. So I switched to other brands and finally I made my own using chips by ATMEL and Intersil or Philips.
Aurel was one that I trusted before.
Now, as I see it, $55 is %01010101 and $AA is %10101010, so if the PIC catches somewhere in the middle the string it cannot distiguish whether is a 55 or AA or something else.
May be you can try a different start character instead of $AA.
Ioannis
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