Hi,
I am using multiple GPRS Shield V2 in a project with Arduino Mega 2560 to send data to a web server.
After a few week/month of working properly I start to have an issue with the shields.
The Arduino is powered from a 12V battery using a SJ-WYUCB DC 5V USB Tension Step Down Module (3A) from dx.
This shield stop when I am sending the AT command :
AT+CIPSTART="TCP","example",80
I did the following test :
- Connect the Arduino Mega with the GPRS Shield V2 to my computer (macbook pro)
- Load the following code to the Arduino (this code is from the wiki page GPRS_Shield_V2.0):
//Serial Relay - Arduino will patch a
//serial link between the computer and the GPRS Shield
//at 19200 bps 8-N-1
//Computer is connected to Hardware UART
//GPRS Shield is connected to the Software UART
#include <SoftwareSerial.h>
SoftwareSerial GPRS(7, 8);
unsigned char buffer[64]; // buffer array for data recieve over serial port
int count=0; // counter for buffer array
void setup()
{
GPRS.begin(19200); // the GPRS baud rate
Serial.begin(19200); // the Serial port of Arduino baud rate.
}
void loop()
{
if (GPRS.available()) // if date is comming from softwareserial port ==> data is comming from gprs shield
{
while(GPRS.available()) // reading data into char array
{
buffer[count++]=GPRS.read(); // writing data into array
if(count == 64)break;
}
Serial.write(buffer,count); // if no data transmission ends, write buffer to hardware serial port
clearBufferArray(); // call clearBufferArray function to clear the storaged data from the array
count = 0; // set counter of while loop to zero
}
if (Serial.available()) // if data is available on hardwareserial port ==> data is comming from PC or notebook
GPRS.write(Serial.read()); // write it to the GPRS shield
}
void clearBufferArray() // function to clear buffer array
{
for (int i=0; i<count;i++)
{ buffer[i]=NULL;} // clear all index of array with command NULL
}- Open the Serial Monitor of the Arduino App and type the following AT command :
AT+CGATT?
+CGATT: 1
OK
AT+CIPMUX=0
OK
AT+CIPSHUT
SHUT OK
AT+CSTT="example.m2m","",""
OK
AT+CIICR
OK
AT+CIFSR
123.123.123.123
AT+CIPSTART="TCP","example",80
OK
CONNECô- As you can see the “CONNECT” response is not complete because the shield shutdown (red led go OFF) at this point (just after the AT+CIPSTART).
I have this problem with multiple GPRS V2 Shields…
Can you help me?