Pro Micro sleep mode / interrupt not working

Projects General Guidance
21

I would be glad to know in what way the sketch of post #7 is fragile. This will help me to improve my sketch.

22

Don't know if anyone cares, but here is the code I run on the Mega to see if the Pro Micro is transmitting.

/* sketch for Mega to receive serial data via HC-12 module

HC-12 wired to Mega board as follows:
  VCC to VCC
  GND to GND
  RX to TX1 (pin 18)
  TX to RX1 (pin 19)
  SET to pin 10
*/
const byte ATModePin = 10; //wired to SET pin of HC12
int receivedData;
void HC12_Channel_005() // Set the HC12 to channel 05
  {
  digitalWrite(ATModePin,LOW); //puts the HC12 into AT Command Mode
  Serial.println("HC-12 in command mode");
  delay(50);
  Serial1.write("AT+DEFAULT");
  delay(500);
  while(Serial1.available())
  {Serial.write(Serial1.read());} //prints response from HC-12
  delay(50);
  Serial1.write("AT+C005"); 
  delay(500);
  while(Serial1.available())
  {Serial.write(Serial1.read());} //prints response from HC-12
  delay(50); 
  digitalWrite(ATModePin,HIGH); //puts HC12 back into regular mode
  Serial.println("HC-12 back in regular mode");
  delay(1000);
  }    
void setup() 
{
pinMode(ATModePin, OUTPUT);
Serial.begin(9600);
Serial.println("\nSerial monitor begin");
Serial1.begin(9600);
Serial.println("Serial1 begin");
HC12_Channel_005();
delay(100);
}
void loop() 
{  
    if (Serial1.available()) 
    {
      receivedData=Serial1.read();
      Serial.print(receivedData);
      Serial.print(" ");
    }    
}