Go Down

Topic: Cheap GSM module (SIM800) not connecting to the network (Read 141057 times) previous topic - next topic

kuruki

What power connection do you have?
I have it connected to a 4xAA battery pack with a regulator between them to drop down the voltage to around 4.2 V. I believe it should be giving enough current to work properly. :/

Clemens

You may try out this AT commands:
http://m2msupport.net/m2msupport/sms-at-commands/

There are a lot of other debug examples. Don't know it is helping you.

nikola1010

I have the same problem but also every once and then SIM800L outputs on it's own:

Code: [Select]

+CFUN: 1

+CPIN: READY

Call Ready

SMS Ready

Call Ready

SMS Ready


What could be the issue?

kuruki

I'd get those "Call Ready" and "SMS ready" too sometimes. Glad to know I'm not the only one with the problem. Which country did you try this in if I may ask?

nikola1010

Croatia.

I asked my ebay seller to tell me if they are locked on China network or something, but didn't get any useful information.

nickiskr

I have the same problem.
The module is rebooted and is not registered on the network with newer SIMcard 4G.
Sometimes it works without any problems with old SIMcard 3G.
I'm from Russia. Sim800L.

tomsoft

I got one of these to.

What I see, is that I can not dial , I always have the "no network" error

but:
- I can send and receive SMS
- I have the "ring" signal if I call the SIM


I use a prepaid Orange Sim card for france

Not sure if this hep, would be happy to get more info on this....

oscardec

Hello.

Try changing the position of your sim card.

This is a very common error.

Best regards.

kuruki

That was definitely not it, since the SIM card was getting recognized by the module.

devinger

I also have this problem with a different breakout board. The weird thing is, when I put in a different sim, the module suddenly does work.

karamelo

Well I've received exactly the same module as the youtube video, but looking at the data sheet, it specifically says that the power input should be around 4V-2A, just bought a adjustable DC-DC converter with an LM2596:

http://www.aliexpress.com/item/1pcs-LM2596-LM2596S-DC-DC-3-40V-adjustable-step-down-power-Supply-module-NEW/1116954291.html

The data sheet also mentions that the data lines should have a max voltage of 2.8V. And a suggested circuit for adapting from 3.3V to 2.8V appears on page 31 of the hardware design guide:

http://simcomm2m.com/UploadFile/TechnicalFile/SIM800L_Hardware_Design_V1.00.pdf

So I think that connecting this directly to an arduino possibly isn't the right choice... The power supply doesn't provide enough current and data lines need some circuitry in order to work.

theanat2010

I have the same problem in registration the sim to the network the AT command are working properly until I use AT+cmgs=......
ctrl+z ...send amsg then it return error


I use orange ..jordan network

Egad

I have been working on a home alarm project for a while. I think I can answer some of the questions here on this thread...

Through my work, I have been using this AT-Command manual for Sim800 - https://www.adafruit.com/datasheets/sim800_series_at_command_manual_v1.01.pdf


I have the same problem but also every once and then SIM800L outputs on it's own:

Code: [Select]

+CFUN: 1

+CPIN: READY

Call Ready

SMS Ready

Call Ready

SMS Ready


What could be the issue?

For me, this happens when I send an AT-command before the module gets contact with the network. The Call/SMS Ready are then sent as the module connects to the network.

When I wait for the module to connect before I send my first AT-command, I do not get such messages.





Well I've received exactly the same module as the youtube video, but looking at the data sheet, it specifically says that the power input should be around 4V-2A, just bought a adjustable DC-DC converter with an LM2596:

http://www.aliexpress.com/item/1pcs-LM2596-LM2596S-DC-DC-3-40V-adjustable-step-down-power-Supply-module-NEW/1116954291.html

The data sheet also mentions that the data lines should have a max voltage of 2.8V. And a suggested circuit for adapting from 3.3V to 2.8V appears on page 31 of the hardware design guide:

http://simcomm2m.com/UploadFile/TechnicalFile/SIM800L_Hardware_Design_V1.00.pdf

So I think that connecting this directly to an arduino possibly isn't the right choice... The power supply doesn't provide enough current and data lines need some circuitry in order to work.
I fixed the RX/TX issue by putting a zener to lower the arduino TX signal. Like here: http://wiki.groundlab.cc/doku.php?id=microcontrollersgsm


The other line is good to go; the arduino senses 2.8V signals.

I also got my 4V power source by lowering the arduino 5V with a zener.




I have the same problem in registration the sim to the network the AT command are working properly until I use AT+cmgs=......
ctrl+z ...send amsg then it return error


I use orange ..jordan network
I do not really understand, but if you communicate directly with the module (through terminal) there is no way (if there is, I have missed it) to send <ctrl+z> as this is char no.26 (GSM charset)
My workaround was this:   (a slight modification of the SoftwareSerial example)
Code: [Select]

void loop() // run over and over
{
  if (mySerial.available())
    Serial.write(mySerial.read());
  if (Serial.available()){
    char c = (char)Serial.read();
    if(c == '#')
        mySerial.write((char)26);
    else
        mySerial.write(c);
  }
}


Hope this will help you!

//Egad

hasard

Don't forget ; character if you try to call:
ATD+7916XXXXXXX;

simonsmart99



Hi All

I have exactly the same problem with a similar module:

http://www.ebay.co.uk/itm/New-SIM800L-GPRS-GSM-Module-SIM-Board-Quadband-L-shape-Antenna-for-MCU-Arduino-/161698611153?hash=item25a5fcffd1

I have a 2Amp 5v regulated supply powering the unit, so no power problems here.

Here is the response I get when trying to register:

AT+COPS=?
+COPS: (2,"vodafone","voda UK","23415"),(3,"T-Mobile","TMO UK","23430"),(3,"O2","O2 -UK","23410"),,(0-4),(0-2)

OK

AT+COPS?
+COPS: 1

OK


And when I try to register to the Vodafone network manually:
 
AT+COPS=1,0,"vodafone"
ERROR


So it seems very much as if the module is unable to connect to UK networks.

ANY INPUT WOULD BE GREATLY APPRECIATED.

Kind regards
Simon



Go Up