Hi Everybody;

Let me tell you, one of my observation;
i checked the voltage levels at RXD and TXD pins of the mobile phone in both normal and cross-over connections:

in normal connection:

* RC6/TX -> T2IN AND T2OUT -> PIN2 RXD;
PIN2 has negative voltage around 7 or 8 Volts,
When signal comes from pic , it makes a sudden change

* RC7/RX -> R2OUT AND R2IN -> PIN3 TXD
PIN3 has 0 voltage,
When signal comes from pic , it does not make a sudden change


i tried also cross-over connection;

* RC6/TX -> T2IN AND T2OUT -> PIN3 TXD
PIN3 has negative voltage around 6 or 7 Volts,
When signal comes from pic , it makes a sudden change

* RC7/RX -> R2OUT AND R2IN -> PIN2 RXD
PIN2 has negative voltage around 5 or 6 Volts,
When signal comes from pic , it does not make a sudden change

Do you have any idea, what is going on ?