GPRS Shield does not work

[bzuk]

hello,
I bought GPRS Shield but does not work as it should, still on it flashes netlight in 1s interval, as if not unlogged simcard, but simcadr is off the PIN, I think there is a bug in SIM900, could you help me what should I do?
here is a video of how it works: http://www.satdoma.eu/sd/video.php

[Irene]

Dear friend,
We are sincerely sorry for the inconvenience caused you.
But I have to tell you that all our products are 100% tested before shipping out.
We are always on your side and trying our best to help you to solve it because we are serious sellers.Your satisfaction is our pursuit.
Let's get to the point now.Please be a little patient and try the following steps:
1.Mega2560 doesn't support d8,d9.We recommend you to use a UNO to have a try.
2.Please check if there is something wrong with your firmware.you can send it to us to check.
Please tell us the results after you tested.We will confirm it and give you further solution.
Look forward to your early reply.
Best regards

[bzuk]

hello,
ATmega2560 is 100%, I already had one at home GPRS Shield and work under this fw:



#include <SoftwareSerial.h>
SoftwareSerial SIM900(7, 8); // configure software serial port

void setup()
{
SIM900.begin(19200);
SIM900power();
delay(20000); // give time to log on to network.
}

void SIM900power()
// software equivalent of pressing the GSM shield "power" button
{
digitalWrite(9, HIGH);
delay(1000);
digitalWrite(9, LOW);
delay(5000);
}

void callSomeone()
{
SIM900.println("ATD + +421XXXXXXXXX;"); // dial
delay(100);
SIM900.println();
delay(30000); // wait for 30 seconds...
SIM900.println("ATH"); // hang up
}

void loop()
{
callSomeone(); // call someone
SIM900power(); // power off GSM shield
do {} while (1); // do nothing
}


new this does not work, but the main fault is that the sim not log into the network, Netlight LED after logging is flashing 1x 3s but I blink 1x 1s, this indicates that it is not a network logged
Here is a second video behavior under external power, as it behaves LED netlight: http://www.satdoma.eu/sd/video.php
and here is the video how should behave LED netlight: https://www.youtube.com/watch?feature=p ... z1YPsbIgRg,
problem will be between SIM900 and simcard

[observing]

@bzuk:
There may be other problems with your setup or the shield, but you should pay attention to the fact that you can't use pin D7 on the ATmega2560 as RX in the SoftSerial library. This is discussed in the description of the SoftSerial library (http://arduino.cc/en/Reference/SoftwareSerial) and on the shield's wiki page (http://www.geeetech.com/wiki/index.php/ ... PRS_Shield). Since this specific shield only supports pin D7 as RX for the SoftSerial library, you can't communicate between the ATmega2560 and the shield using Software Serial. You should be able to communicate between them using Hardware Serial.

[bzuk]

ok, so I threw out mega2650 I used for communication with the FT232 module 5V, communication works but simcard is not logged in the network as seen in another video:
http://www.satdoma.eu/sd/video.php

what is the problem? what is the problem? SIM PIN is disabled

[Alex-w]

Dear friend
does it means the gprs field does not work with Hardware Serial?Then you must make sure these things:
1.sim crad does plug in
2.netlight 64ms on,300ms off
3.check the power key does work

[bzuk]

hello,
works also HWserial and SWserial, power key works, I know them on and off red status LED, something must be communication between sim and SIM900

[jafarin]

I have similar problem and I dont get access to gsm network. Reason is bad network, because I have problems with my samsung phone in this area.

Anyway, I tested my gsm shield as far as I could, until I go home, where network will be much better.

To check will SIM work run next AT command :
at+cpin?

response should be READY, what means pin has open or it is given.
If not there is something wrong with SIM. Study AT-commands documentation found from GSM Shield wiki page. AT+CPIN command gives possibility to give PIN or change it, if shield have connection to SIM card.

If SIM is ok, next to check is access to network and that you get with next AT command:
AT+CSQ

With this command you can see what is signal quality. It should be something else than 0,0. If it is, check with next command what is registration status.
AT+CREG?

I hope you get some information and get more out from your shield. I am new with arduino and electronic. My backround is more software and networks. All this information I get by study SIM900 AT-commands and HW manuals. Also I have old analog modem knowledge from begin of 1990. If you get some responses, copy them here. I will look them or some one else who is quicker .

-Jafarin

[Alex-w]

i think you’d better check these things：
1.check the sinal quality
AT+CSQ
2.check the network operator
AT+COPS=?
3.check the sim card
AT+CPIN?

AT+CFUN

4.enter the engineering mode，check network
AT+CENG=2

5.check NETWORK REGISTRATION
AT+CREG?

[bzuk]

ok so here is a listing of what you sent commands, from power on GPRS:
˙˙˙˙
RDY

+CPIN: NOT INSERTED

+CFUN: 1
AT+CSQ

+CSQ: 17,0

OK
AT+COPS=?

+COPS: (1,"O2 - SK","O2 - SK","23106"),(1,"Orange AT","Orange A","23205"),(2,"Orange SK","Orange","23101"),(1,"T-Mobile SK","TMO SK","23102"),(1,"A1","A1","23201"),(1,"T-Mobile Austria","TMA","23203"),,(0,1,4),(0,1,2)

OK
AT+CPIN?

ERROR
AT+CFUN

ERROR
AT+CREG?

+CREG: 0,0

OK
AT+CENG=2

OK
+CENG:0,"0884,30,99,1665,15,02,2ad5,05,00,ffff,255"
+CENG:1,"0639,15,39,232,05,bcc"
+CENG:2,"0633,13,05,232,05,bcc"
+CENG:3,"0878,13,128,232,05,bcc"
+CENG:4,"0644,09,167,232,05,bcc"
+CENG:5,"0034,50,153,231,02,1"
+CENG:6,"0017,48,157,231,01,b"
+CENG:0,"0884,31,99,1665,15,02,2ad5,05,00,ffff,255"
+CENG:1,"0639,15,39,232,05,bcc"
+CENG:2,"0633,13,05,232,05,bcc"
+CENG:3,"0878,13,128,232,05,bcc"
+CENG:4,"0644,09,167,232,05,bcc"
+CENG:5,"0034,50,153,231,02,1"
+CENG:6,"0017,48,157,231,01,b"
+CENG:0,"0884,31,99,1665,15,02,2ad5,05,00,ffff,255"
+CENG:1,"0639,15,39,232,05,bcc"
+CENG:2,"0633,13,05,232,05,bcc"
+CENG:3,"0878,13,128,232,05,bcc"
+CENG:4,"0644,09,167,232,05,bcc"
+CENG:5,"0034,50,153,231,02,1"
+CENG:6,"0017,48,157,231,01,b"
+CENG:0,"0884,31,99,1665,15,02,2ad5,05,00,ffff,255"
+CENG:1,"0639,14,39,232,05,bcc"
+CENG:2,"0633,13,05,232,05,bcc"
+CENG:3,"0878,13,128,232,05,bcc"
+CENG:4,"0644,09,167,232,05,bcc"
+CENG:5,"0034,50,153,231,02,1"
+CENG:6,"0017,48,157,231,01,b"
+CENG:0,"0884,31,99,1665,15,02,2ad5,05,00,ffff,255"
+CENG:1,"0639,13,39,232,05,bcc"
+CENG:2,"0633,13,05,232,05,bcc"
+CENG:3,"0878,13,128,232,05,bcc"
+CENG:4,"0644,09,167,232,05,bcc"
+CENG:5,"0034,50,153,231,02,1"
+CENG:6,"0017,48,157,231,01,b"
+CENG:0,"0884,31,99,1665,15,02,2ad5,05,00,ffff,255"
+CENG:1,"0639,13,39,232,05,bcc"
+CENG:2,"0633,13,05,232,05,bcc"
+CENG:3,"0878,13,128,232,05,bcc"
+CENG:4,"0644,09,167,232,05,bcc"
+CENG:5,"0034,50,153,231,02,1"
+CENG:6,"0017,48,157,231,01,b"
+CENG:0,"0884,31,99,1665,15,02,2ad5,05,00,ffff,255"
+CENG:1,"0639,14,39,232,05,bcc"
+CENG:2,"0633,13,05,232,05,bcc"
+CENG:3,"0878,13,128,232,05,bcc"
+CENG:4,"0644,09,167,232,05,bcc"
+CENG:5,"0034,50,153,231,02,1"
+CENG:6,"0017,48,157,231,01,b"
...
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