why dont show mySerial in Serial monitor when i use interrupt function?

Projects Programming
1

Hi serve professionals dear
I use sim 808 for receive sms and call , in normally state (without use interrupt) in serial monitor show detail of sms and call but when i use interrupt dont show any thing in my serial monitor :frowning:

I use RI Behavior for interrupt:

RI: this pin will tell you whether the module is on and is there any calls and messages received. It will be pulled to high level when the module is on. And it will change to low for 120ms when a call or message is received.

i use RI Behavior for interrupt that detect a new message or call is has arrived
attachInterrupt(digitalPinToInterrupt(interruptPin), check, LOW)

this is my code without interrupt :

#include <SoftwareSerial.h>

SoftwareSerial mySerial(10, 11); // RX, TX
const byte interruptPin = 3;

void setup()
{
  // Open serial communications and wait for port to open:
 // attachInterrupt(digitalPinToInterrupt(interruptPin),check,LOW);
  Serial.begin(9600);
  mySerial.print("AT+CMGF=1\r");  // set SMS mode to text
  delay(1000);
  mySerial.print("AT+CNMI=2,2,0,0,0\r"); 
  // blurt out contents of new SMS upon receipt to the GSM shield's serial out
  delay(100);




  // set the data rate for the SoftwareSerial port
  mySerial.begin(9600);
 // mySerial.println("Hello, world?");
}

void loop() // run over and over
{
  check();
  /*if (mySerial.available())
    Serial.write(mySerial.read());
  if (Serial.available())
    mySerial.write(Serial.read());*/
}


void check(){
  //Serial.println("test");
  if (mySerial.available())
    Serial.write(mySerial.read());
  if (Serial.available())
    mySerial.write(Serial.read());
}

and this is my serial monitor when i send sms "hello" to sim808:

+CMT: "+989378171477","","17/04/04,13:31:01+18"
Hello

this is my cod with interrupt and i dont see any thing in Serial monitor:

#include <SoftwareSerial.h>

SoftwareSerial mySerial(10, 11); // RX, TX
const byte interruptPin = 3;

void setup()
{
  // Open serial communications and wait for port to open:
  attachInterrupt(digitalPinToInterrupt(interruptPin),check,LOW);
  Serial.begin(9600);
  mySerial.print("AT+CMGF=1\r");  // set SMS mode to text
  delay(1000);
  mySerial.print("AT+CNMI=2,2,0,0,0\r"); 
  // blurt out contents of new SMS upon receipt to the GSM shield's serial out
  delay(100);




  // set the data rate for the SoftwareSerial port
  mySerial.begin(9600);
 // mySerial.println("Hello, world?");
}

void loop() // run over and over
{
  //check();
  /*if (mySerial.available())
    Serial.write(mySerial.read());
  if (Serial.available())
    mySerial.write(Serial.read());*/
}


void check(){
  //Serial.println("test");
  if (mySerial.available())
    Serial.write(mySerial.read());
  if (Serial.available())
    mySerial.write(Serial.read());
}

I have to use interrupt in my project !
please help me

2

What, EXACTLY, is generating the external interrupt?

Why the heck are you using LOW as the mode? That is generally used ONLY to wake up a sleeping Arduino.

If the pin is normally LOW, you will spend ALL of your time in the interrupt handler, and NO time getting data on the software serial port.

3

PaulS:
What, EXACTLY, is generating the external interrupt?

Why the heck are you using LOW as the mode? That is generally used ONLY to wake up a sleeping Arduino.

If the pin is normally LOW, you will spend ALL of your time in the interrupt handler, and NO time getting data on the software serial port.

i use external interrupt,
RI pin is normaly HIGH but when receive call or sms go to LOW level

the image of below is RI behavior and sim808:

4

Two things occur to me

Your attachInterrupt should be "FALLING" rather than LOW

And your Interrupt Service Routine check() should simply note the fact that the interrupt has occurred - like this#

void check() {
  newInterrupt = true;
}

and then your code in loop() can check to see the value of newInterrupt and do whatever printing is needed. It will then set newInterrupt back to false ready for the next interrupt.

Do not include print instructions in an ISR as they are slow and require interrupts to be enabled.

...R