Hello guys!
I have the following problem.
See the code below:
#include <SoftwareSerial.h>
SoftwareSerial gsm(2, 3);
int8_t answer;
int8_t answer2;
char frame[200];
char SMS[200];
int x;
unsigned long previous3;
String mystring;
void setup()
{
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}
gsm.begin(9600);
Serial.println("Connecting to the network...");
while( (sendATcommand("AT+CREG?", "+CREG: 0,1", 500) ||
sendATcommand("AT+CREG?", "+CREG: 0,5", 500)) == 0 );
Serial.println("Connection established...");
sendATcommand("AT+CMGF=1", "OK", 1000); // sets the SMS mode to text
sendATcommand("AT+CNMI=2,1,0,0,0", "OK", 2000);
sendATcommand("AT+CMGD=1", "OK", 2000);
sendATcommand("AT+CMGD=2", "OK", 2000);
}
void loop(){
read_SMS(); //reads SMS
if(millis() - previous3 > 10000){
sendATcommand("AT+CMGDA=\"DEL ALL\"" , "OK", 2000);
previous3 = millis ();
}
}
int8_t read_SMS(){
answer2 = sendATcommand("AT+CMGR=1", "+CMGR:", 2000);
if (answer2 == 1)
{
answer2 = 0;
while(gsm.available() == 0);
// this loop reads the data of the SMS
do{
// if there are data in the UART input buffer, reads it and checks for the asnwer
if(gsm.available() > 0){
SMS[x] = gsm.read();
x++;
// check if the desired answer (OK) is in the response of the module
if (strstr(SMS, "OK") != NULL)
{
answer2 = 1;
}
}
}while(answer2 == 0); // Waits for the asnwer with time out
SMS[x] = '\0';
Serial.println("Received message: ");
Serial.println(SMS);
else
{
Serial.print("error ");
Serial.println(answer, DEC);
}
}
int8_t sendATcommand(char* ATcommand, char* expected_answer, unsigned int timeout){
uint8_t x=0, answer=0;
char response[100];
unsigned long previous;
memset(response, '\0', 100); // Initialize the string
delay(100);
while( gsm.available() > 0) gsm.read(); // Clean the input buffer
gsm.println(ATcommand); // Send the AT command
x = 0;
previous = millis();
// this loop waits for the answer
do{
if(gsm.available() != 0){
// if there are data in the UART input buffer, reads it and checks for the asnwer
response[x] = gsm.read();
// positions[x]=response[x];
x++;
// check if the desired answer is in the response of the module
if (strstr(response, expected_answer) != NULL)
{
answer = 1;
}
}
// Waits for the asnwer with time out
}while((answer == 0) && ((millis() - previous) < timeout));
return answer;
}
In main loop there is only function read_SMS(); which continuously checks if new MSG was received.
When I send my first SMS after Arduino was reset, it reads the first msg just fine, then after 10 seconds it deletes it from memory. After that I send my 2nd SMS and here is where problem occurs. Actually 2nd msg was received and stored, but the SMS[] array stayed the same, so I still read the same 1st msg.
Example: my first msg from my cell phone to GSM module:
Received message:
"REC UNREAD","+3**********","","16/06/22,11:31:31+12"
Hello
my second msg was "Bye" but it still displayed same thing above. It keeps going for all messages afterwards (i.e. third, fourth etc.) till I reset my Arduino.
Is there any special way I should clear out SMS[] parameter on each cycle? Thank you in advance!
