OHS-SMS

[Jonathan]

Hello,
Has anyone had trouble configuring sending SMS. My Giffgaff card will not connect, although it works fine on another 3g modem.

Regards
Jonathan.

[vysocan]

Hi Jonathan,

SIM800C is only 2G modem.

[Jonathan]

Hi
Yes I know sim800c is only 2G. My Giffgaff  has been used on  other 2G modems.

[vysocan]

Is it correctly registered to GSM network?
Does the SIM have no PIN setup?

[Jonathan]

Hello
   Yes it is registered to o2 Network. And it does not have a pin. In fact another SIM arrived this morning
that was registered ,£10.00 stuck on it, and that does not work either.
Both cards work in my phone.

Kr
Jonathan

[Jonathan]

Hi
Just tried EE sim as well, that will not register either.(Thats the one out of my mobile by the way)

Kr

Jonathan

[vysocan]

Hello,

on Global tab you can see the status:

It is
- Version of modem.
- if the modem is On.
- if the modem respond to AT commands.
- Network status.
- Signal strength.

All modems are four band, they should work on GSM 2G network in all countries. Not sure what it can be.

One reason would be, if you really have 2G compatible SIM card(s).

And second, stupid question, is the antenna plugged in?

[Jonathan]

https://community.giffgaff.com/t5/Help-Support/Is-giffgaff-still-running-a-GSM-2G-network/td-p/20876762

And I have tried at least 7 different antenna. Internal and external.

Kr

Jonathan

[vysocan]

What do you suggest now?

Can you solder? I tell you how to bypass the UART lines and if you have 3V3
serial you can solder 2 wires, add 2 jumper wires and try to speak directly
to GSM module.

Or here is part of code that try periodically to initialize GSM:

// GSM modem check
if (_counter == 15) {
// look if GSM is free
if (nilSemWaitTimeout(&GSMSem, TIME_IMMEDIATE) != NIL_MSG_TMO) {
GSMisAlive = GSM.ATsendCmd(AT_is_alive);
if (GSMisAlive == 1) {
if (!GSMsetSMS) {
//GSMsetSMS = GSM.ATsendCmd(AT_CLIP_ON); // CLI On
GSMsetSMS = GSM.ATsendCmd(AT_set_sms_to_text); // set modem to text SMS
format
if (GSMsetSMS) GSMsetSMS = GSM.ATsendCmd(AT_set_sms_receive); // Set modem
to dump SMS to serial
GSM.ATsendCmdWR(AT_modem_info, (uint8_t*)modem_info);
}
_resp = GSM.ATsendCmdWR(AT_registered, _text, 3);
GSMreg = strtol((char*)_text, NULL, 10);
_resp = GSM.ATsendCmdWR(AT_signal_strength, _text, 2);
GSMstrength = (strtol((char*)_text, NULL, 10)) * 3;
} else { GSMreg = 4; GSMstrength = 0; GSMsetSMS = 0;}
nilSemSignal(&GSMSem); // Exit region.
if (_GSMlastStatus != GSMreg) { // if modem registration changes log it
_GSMlastStatus = GSMreg;
_tmp[0] = 'M'; _tmp[1] = GSMreg; _tmp[2] = GSMstrength; pushToLog(_tmp, 3);
}
}
}


I can maybe compile special firmware to put more text to Debug tab.

Or you can also verify by ohmmeter the antenna wire. When GW is turned off.
One tip to GSM module pad and second tip to end of pigtail. The
connector(s) may be loose, I've seen it before.

Adam

[Jonathan]

Hi Adam
  Did you get the photos of the UFL socket orientation..?
Kr
Jonathan

[vysocan]

Hello Jonathan,

yes, :( sorry it really looks like I put wrong way. The pin is connected only to the leg that comes from under the U.FL connector.

Do you have equipment to fix it? Hot air gun is best.

Adam

[Jonathan]

Its going, got the UFL connector off OK, but removing the surplus solder off it caused the ring to break away. Just made an antennae of copper wire, soldered that onto pin 32 and its sending me texts :-)

[Jonathan]

SMS begin: 1
SMS sent: -21
Page begin: -11
Email -GSM len: 8>+CMGS: 2<
-GSM len: 0><
-GSM len: 2>OK<
OK
Email End
Alert end
>Radio A:20,Data 25,53-54-0-11-C7-97-41-56-0-99-E9-77-40-58-0-0-0-16-42-44-0-0-0-0-0-RSSI:-27

[vysocan]

That is awesome, really. Sorry again for the problem.

I'll put here the image, since it is just nice work.