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Tips and questions relating to the GPS modules from SFE
By Koen Dobbels
#42887
Hello,

I use the GM862-GPS and have some trouble sending SMS messages.

I want f.i. to send using Hyperterminal the SMS "hellohello" in unicode format: 0068006f006c006c006f00680065006c006c006f.

In PDU mode, this can be done as follows:
AT+CMGF=0
OK
AT+CMGS=34
>0011000B9123**********0008AA1400680065006C006C006F00680065006C006C006F
(with ********** my international phone number)

This messages arrives as "hellohello" as it should.


However, if I try to send the SMS in text mode as follows:
AT+CMGF=1
OK
AT+CSMP=17,167,0,8
OK
AT+CMGS=+32*********
>00680065006c006c006f00680065006c006c006f

then this message arrives as "00680065006c006c006f00680065006c006c006f" as where I expect "hellohello".

What am I doing wrong?
I used the same code on other GSM Modems and there it worked fine.

Thanks.
By jasonharper
#42910
In text mode, you're supposed to send text. "hellohello" is what you should send if "hellohello" is what you want to receive.
By Koen Dobbels
#42917
Jason,

Thanks for your reply, but it is not true for all gsm modules.
In the command "at+csmp=17,167,0,8", the '8' means coding scheme UCS2 is to be used, which implicates that the text to be sent should be formatted as 16bit.
And thus theoretically not "hellohello" should be send, but the hex representation of the same text, which is "00680065006c006c006f00680065006c006c006f".

I used this method before with other modules to sent chinese, korean, arabic, etc characters (f.i chinese 昧 is 6627(hex)).

Is there any way of sending this type of characters without switching the GM862 module to PDU mode?
By jasonharper
#42919
As far as I can tell, the Telit modules use only the AT+CSCS command to determine how to interpret text - you'd need to set that to "UCS2" to be able to enter the hex-encoded Unicode in your example. The last parameter of AT+CSMP is only used to construct the PDU from the text.
By noceco33
#45676
Koen Dobbels wrote:

However, if I try to send the SMS in text mode as follows:
AT+CMGF=1
OK
My problem is similar, Im trying the same but I don´t know how to finish the text messenge..

I mean..
AT+CMGF=1 -> for the Text format
AT+CSMP=17,167,0,0 -> some config

and when I try to write the SMS...

AT+CMGS="**tel num***"
this comand appear ">"

> ... I introduce here the text, but I dont know how to finnish it

In the manual appear "Press CTRL-Z" but with my serial terminal that is Undo (like copy, paste, cut...) so, the device still waiting and waiting.
and I can´t send that SMS...

I knot that is going to be a small mistake, but please help me!!!!!!!!!

pleaseeee. hehe