How to send GSM international phone code?

[Jan Lichtenbelt]

I use the maco SendTextMessage to send a SMS to a moble phone. This works OK for national phone numbers. But if I use +44 (for UK) or +31 (for NL), it does not work.

How to handle this?

kind regards

Jan

[chipfryer27]

Hi

I haven't used the GSM component so I am not best placed to answer but one thing you could try is using 00 instead of "+". I know the "+" is supposed to be universal but it is worth trying 0044 or 0031. ITU has specified 00 as international access but not all countries have adopted it.

Regards

[Jan Lichtenbelt]

Hi Chipfreyer27,

Thanks for your suggestion for improvements.

I found that the problem was a hardware problem. The +31 (or general +country code) plus phone number (without preceeding 0) works fine.

But I have an other question
I used the flowcode as attached. There is one problem. To send a SMS I used the SendTextMassage. But I found even the SMS has correctly be received, the return value of SendTextMessage is 255 (failure) instead of 0 (succes). I found this problem all the time. What can be the reason and how can this be improved?

Kind regards

Jan

SIM800_HOLA_V5a.fcfx

(17.96 KiB) Downloaded 218 times

[chipfryer27]

Hi

I haven't played with the GSM component so I'm perhaps not best placed to answer. I have however found that a colleague has a similar module to the EB board so maybe I will steal that when he isn't looking

I can think of two possible reasons and I stress that both could be completely wrong, but here goes anyway.

The component macro may possibly be looking for a specific reply from the board to indicate success. Possibly the version of your board provides a different reply? A few years ago that was the case with some ESP WiFi modules I was using. Manufacturer changed firmware and they were no longer compatible with the macro. Kersing very kindly created a macro that I could use that allowed me to change the expected response. I'm not saying that is your problem but perhaps a possibility. Have you tried connecting with a PC running a terminal program and sending "AT" commands to see what the module replies with or monitoring the Rx port with an PC/analyser? That may be worthwhile.

Next, and I stress I don't know how the component operates, or how long does it wait for a reply and what triggers this reply. It returns 0 for success but what triggers the response? Is it that the module has received your send command, the module has sent your text or that the module has received a network receipt? Apart from the former these could be seconds. Just a (probably wrong) thought.

Regards

[Jan Lichtenbelt]

Can someone help me with the problem of the error code 255 if a SMS has sent correctly?
I have the feeling that the return code is always 255, independent if the SMS has been sent correctly or not.

Kind regards

Jan

[LeighM]

Hi Jan,
As Chipfreyer27 mentioned ...

The component macro may possibly be looking for a specific reply from the board to indicate success. Possibly the version of your board provides a different reply?

The GSM component was designed for EB066 which uses a Telit GL865
The command set is generic, but there could be some differences between this and your SIM800 that is causing this issue.

[Jan Lichtenbelt]

Hi chipfryer27 and LeighM

Thanks a lot. It is hard to find the UART SIM800L protocol. Up to now I do not find it. But it keeps me busy.

Kind regards

Jan

[LeighM]

Try this ...

[Jan Lichtenbelt]

hi LeighM

Thanks for the reference. That is not easy stuff.

Kind regards

Jan

[chipfryer27]

Hi Jan

If you have a PC with USB to Serial converter and HyperTerminal (or similar), you can connect that across the Tx/Rx pins. You can then monitor in real time what commands are being sent and more importantly what the response is to the command.

I recently obtained one of those modules but as I am still on my travels I won't be able to play for a while yet.

Regards