Quote Originally Posted by ruijc View Post

To protect the hardware i was thinking of placing a 220 Ohms resistor between the RX and the Pic.

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From the Rx outputs , one might consider not to draw more than 1 mA in all circumstances ... so, 4.7k in series, and 100k for an input Pulldown are safe values. 47k in series do not introduce significant noise levels ( 470k then for Pulldown !!! )

Alain