Digital pin to be set 0

Hardware Arduino Due
1

Hello all ,

I have to use the logic of reading a particular pin's status of my external µc connected with the DUE . i.e.,

  1. If the pin status is 1 , send data
  2. If the pin status is 0, do not send data.

What I want is , I have selected the pin 52 as input pin. I want it to be configured 0,initially . Onlly when I connect the external µc and the input pin status changes to 1 ,it should become 1.

I have tried:

int RDY = 52;
  int RDY_STATUS=0;

  pinMode(RDY, INPUT);
  digitalWrite(RDY,LOW); 

  RDY_STATUS = digitalRead(RDY);  //the values that are printed here are always one,                     
  Serial.println(RDY_STATUS);        // [b]can this never be 0 and then later changed by i/p pin to 1.[/b]
  Serial.print("read pin");
  Serial.println(digitalRead(RDY));
  delay(1000);
  if (digitalRead(RDY) == HIGH)  
  { 
  
  code continues
  }
2

You should declare RDY pin with a pinMode(DRDY, OUTPUT) and then you can read or write to this pin.

3

But, the rdy pin is actually input pin to the DUE. This is like the SPI data flow control pin.
If I configure it as output ,will it still work according to the pin status it receives ?

4

What prevents you from trying?

5

As I said earlier , according to the datasheet , the pin,I want to read from the external µc is supposed to be INPUT to Arduino. And I did not understand the logic of pinMode(RDY, OUTPUT). So,I would like to know.