jsl123
Newbie level 2
Hello All, hello ckshivaram 
I've a (semi) working solution with an embedded system and a SIM900 GSM modem here.
Everything (sending/receiving SMS) works fine if I use a "local" SIM card here. The card may be PIN locked or not, I can use text format mode or PDU mode, everything is fine.
But my problem now is that I've here a card from a provider from another country. This card is activated and roaming is enabled and working.
I can use this card in a mobile and receive/originate voice calls and receive/send SMS with a mobile.
If I try to send an SMS, the SIM900 will become completely unresponsive! Short example from a terminal session:
at+cmgf=1
at+cscs="+YYzzzzzzzzz"
at+cmgs="+AAbbbbbbbb"
Test1
<Ctrl-Z>
And from now on, it seems as if the card is dead. It won't respond to any key (also not to <Ctrl-C>).
Since I can't even execute a "at+cfun=1,1", the only option then is to power-cycle!! :-(
I just found out, that the modem is not completly dead though.
If I enable unsolicted signaling before trying to send the SMS and (voice) call the card when she seems to be stuck, I get a
+CRING: VOICE
!!!
So it's not dead but not accepting any input. I tried to wait for hours, but nothing happens.
What I tried to solve this were different SMSC's. I tried with the original SMSC from the "home provide" in the other country and with the SMSC of the roaming partner here in my country.
But the result is the same... Only if I set the SMSC to for ex. my mobile phone # here. Sending SMS will timeout rather fast with a CMS error 515 (PS busy).
So I think this has something to do with the SMSC. I tried to do the same in PDU mode, but the results were the same. :-(
Do you know of any "incompatibilities" with some SMSC (software)?
Do you need the firmware version? ;-)
OK
at+gsv
SIMCOM_Ltd
SIMCOM_SIM900
Revision:1137B09SIM900M64_ST
OK
Thank you very much for reading and hopefully providing some light on this!
Salut, J"org
I've a (semi) working solution with an embedded system and a SIM900 GSM modem here.
Everything (sending/receiving SMS) works fine if I use a "local" SIM card here. The card may be PIN locked or not, I can use text format mode or PDU mode, everything is fine.
But my problem now is that I've here a card from a provider from another country. This card is activated and roaming is enabled and working.
I can use this card in a mobile and receive/originate voice calls and receive/send SMS with a mobile.
If I try to send an SMS, the SIM900 will become completely unresponsive! Short example from a terminal session:
at+cmgf=1
at+cscs="+YYzzzzzzzzz"
at+cmgs="+AAbbbbbbbb"
Test1
<Ctrl-Z>
And from now on, it seems as if the card is dead. It won't respond to any key (also not to <Ctrl-C>).
Since I can't even execute a "at+cfun=1,1", the only option then is to power-cycle!! :-(
I just found out, that the modem is not completly dead though.
If I enable unsolicted signaling before trying to send the SMS and (voice) call the card when she seems to be stuck, I get a
+CRING: VOICE
!!!
So it's not dead but not accepting any input. I tried to wait for hours, but nothing happens.
What I tried to solve this were different SMSC's. I tried with the original SMSC from the "home provide" in the other country and with the SMSC of the roaming partner here in my country.
But the result is the same... Only if I set the SMSC to for ex. my mobile phone # here. Sending SMS will timeout rather fast with a CMS error 515 (PS busy).
So I think this has something to do with the SMSC. I tried to do the same in PDU mode, but the results were the same. :-(
Do you know of any "incompatibilities" with some SMSC (software)?
Do you need the firmware version? ;-)
OK
at+gsv
SIMCOM_Ltd
SIMCOM_SIM900
Revision:1137B09SIM900M64_ST
OK
Thank you very much for reading and hopefully providing some light on this!
Salut, J"org