пример для двух портов работает

libraries/SoftwareSerial/examples/TwoPortReceive/TwoPortReceive.ino

@@ -20,65 +20,80 @@
  Not all pins on the Elbear Ace-Uno support interrupts,
  so only the following can be used for RX:
  2, 3, 4, 5, 8, 9
-
- created 18 Apr. 2011
- modified 19 March 2016
- by Tom Igoe
- based on Mikal Hart's twoPortRXExample
-
- This example code is in the public domain.
-
  */
 
 #include <SoftwareSerial.h>
+
 // software serial #1: RX = digital pin 2, TX = digital pin 6
 SoftwareSerial portOne(2, 6);
-
 // software serial #2: RX = digital pin 8, TX = digital pin 10
 SoftwareSerial portTwo(8, 10);
 
-void setup() {
-  // Open serial communications and wait for port to open:
+// active port is changed by user button pressing
+volatile bool isPortOneActive = true;
+void btn_pressed_callback(void)
+{
+  // change active port
+  if (isPortOneActive)
+  {
+    portTwo.listen();
+    Serial.println("Port two is listening");
+    isPortOneActive = false;
+  }
+  else
+  {
+    portOne.listen();
+    Serial.println("Port one is listening");
+    isPortOneActive = true;
+  }
+}
+
+void setup() 
+{
+  // Open serial communications and wait for port to open
   Serial.begin(115200);
   while (!Serial) {
     ; // wait for serial port to connect. Needed for native USB port only
   }
 
+  // attach interrupt to user button
+  attachInterrupt(digitalPinToInterrupt(BTN_BUILTIN), btn_pressed_callback, FALLING);
+
   // Start each software serial port
   portOne.begin(57600);
   portTwo.begin(57600);
 
-  portTwo.listen();
-  delay(2000);
+  // First listen to port one
+  portOne.listen();
+  isPortOneActive = true;
+  Serial.println("Port one is listening");
 }
 
-void loop() {
-  // By default, the last initialized port is listening.
-  // when you want to listen on a port, explicitly select it:
-  portOne.listen();
+void loop() 
+{
+  // check data from port one
+  if (portOne.available())
+  {
     Serial.println("Data from port one:");
     // while there is data coming in, read it
-  // and send to the hardware serial port:
-  while (portOne.available() > 0) {
-    char inByte = portOne.read();
-    Serial.write(inByte);
-  }
+    // and send to the hardware serial port
+    while (portOne.available() > 0) 
+      Serial.write((char)portOne.read());
     
-  // blank line to separate data from the two ports:
+    // blank line to separate data from the two ports
     Serial.println();
-  delay(2000);
-
-  // // Now listen on the second port
-  // portTwo.listen();
-  // // while there is data coming in, read it
-  // // and send to the hardware serial port:
-  // Serial.println("Data from port two:");
-  // while (portTwo.available() > 0) {
-  //   char inByte = portTwo.read();
-  //   Serial.write(inByte);
-  // }
-
-  // // blank line to separate data from the two ports:
-  // Serial.println();
-  // delay(2000);
+  }
+
+  // check data from port two
+  if (portTwo.available())
+  {
+    Serial.println("Data from port two:");
+    // while there is data coming in, read it
+    // and send to the hardware serial port
+    while (portTwo.available() > 0) 
+      Serial.write((char)portTwo.read());
+    
+    // blank line to separate data from the two ports
+    Serial.println();
+  }
 }