well.. two things...
first one The Apins works perfectly in the arduino Mega the mistake was that i have selected nano board.... (mmm juyuuu i am discovering how much stupid can i be, no limit for my....)
the second one i have try this sketch:
/*
Prueba de mando R\C
*/
int Ch1Pin =2;
//// variables donde mapeamos la lectura de 0 1024 a 0 256
unsigned long Ch1Var;
//////////////////////////////////////////////////
void setup() {
Serial.begin(9600);
pinMode(Ch1Pin,INPUT);
}
void loop() {
Ch1Var = pulseIn(Ch1Pin,HIGH,200000);
Serial.println("POSITIVO");
Serial.println('Ch1Var,DEC');
Ch1Var = pulseIn(Ch1Pin,LOW,200000);
Serial.println("negativo");
Serial.println('Ch1Var,DEC');
}
and what i have obtain in the serial monitor is read 17731 for high and 17731 for low every time like in the beginning of the post....
well and thing taht i had the dremel in one hand and i was screaming CUT the shield nobody know.... jeje i little idiot...
one more time Thanks for your help and time