first working implementation of timer-based RS485

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

examples/SendAndReceive/SendAndReceive.ino

@@ -0,0 +1,44 @@
+/*
+ This sketch demonstrates, how to use the SoftRS485 library.
+ This library makes use of Arduinos timer 1
+ */
+
+#include <SoftRS485.h>
+
+int count = 0;
+String message = "Message ";
+
+void setup() {
+  Serial.begin(115200);
+
+  init485(2,3,4,5); // library initialization:
+  // connect pin 2 to RO of Max485
+  // connect pin 3 to ^RE of Max485
+  // connect pin 4 to DE of Max485
+  // connect pin 5 to DI of Max485
+
+  if (send485("Test")) {
+    // This should send "Test" if the line is free.
+    Serial.println("Test sent!");
+  }
+  if (!send485("Test2")) {
+    // This shoult fail, as transmission of "Test" should still be on the way
+    Serial.println("Test2 failed!");
+  }
+}
+
+void messageReceived(String message){
+}
+
+void loop(){
+  if (available485()){ // check if we have received anything
+    Serial.print("messageReceived: ");
+    Serial.println(get485Message()); // read the received message
+
+    // send another message everytime we have received one
+    count++;
+    char msg[128];
+    (message+count).toCharArray(msg,128);
+    send485(msg);
+  }
+}