Practical Limits of Serial communications?

Projects Networking, Protocols, and Devices
14

Graynomad:
Check out Serial.available()

Rob

Thanks graynomad,

I had used that in the past. No change in behavior.

/* YourDuino RS485 Slave Node A Example
 terry@yourduino.com */

/*-----( Declare Variables )-----*/
int ledPin=13;
int EN = 6;
byte Val;

void setup()/****** SETUP: RUNS ONCE ******/
{
  pinMode(ledPin, OUTPUT );
  pinMode(EN, OUTPUT );
  Serial.begin (9600);
  Serial.println("Setup Complete.");
}//--(end setup )---

void loop()  /****** LOOP: RUNS CONSTANTLY ******/
{
  // receive Data
  digitalWrite (EN, LOW ); // enable receive
  if (Serial.available()>0) {
    Val = Serial.read ();
    if ( 'A' == Val) 
    {
      digitalWrite (ledPin, HIGH );
      delay (500);
      digitalWrite (ledPin, LOW );
      delay (500);
    }
  else Serial.println(Val);
  }
}//--(end main loop )---

I get a "Setup complete" and then nothing on the slave. I get some chatter on the slave as I connect and disconnect the master. I re-verified electrical continuity from one RS485 to the other. Enabling / Disabling the terminators does nothing either. I'm feeling rather blue, I must say.