EM7511 Receive SMS in PDU not possible?

IoT Modules MC/EM Series
1

I’m evaluating the EM7511 for its SMS capabilities and have run into a problem. The modem sends PDU SMS messages just fine, but I’m having trouble getting it to receive SMS in PDU mode.

Here’s the problem:

  • New SMS notifications arrive as unsolicited messages of the form: $QCMTI: … (undocumented)
  • They should be arriving as: +CMTI: … (documented)
  • Reading these messages with the standard AT+CMGR FAILS. They are not stored in storage as defined by AT+CPMS (AT+CMGL shows an empty list). Where are these messages?
  • Apparently, there are a number of undocumented commands that start with AT$Q… So extrapolating from that, reading these messages with AT$QCMGR does WORK. However, they are ALWAYS in text mode.
  • The problem is: AT$QCMFG=0 FAILS. It does not support PDU mode, only text.

Why are there so many apparently undocumented commands for SMS receiving on this modem, which you are forced to use to receive messages? Am I missing the documentation for these somewhere?

How can this modem receive PDU SMS messages, which is necessary for concatenation, for example? This appears to be impossible from my testing with the undocumented commands.

I’m on the latest Verizon firmware in the US.

Thank you,
Alex :nerd_face:

2

@alex5

So the at$q commands are all proprietary Qualcomm commands and they are undocumented because we do not officially support or maintain them. They are in the code base hence they react but there is no guarantee of their operation. Blocking them is additional work and could have unforeseen side effects hence we just don’t document them.

Re PDU mode, it seems to work for me using standard 3GPP AT commands.

ati
Manufacturer: Sierra Wireless, Incorporated
Model: EM7565
Revision: SWI9X50C_01.11.00.00 5ba42f jenkins 2019/06/28 09:51:52
MEID: 35926008010890
IMEI: 359260080108902
IMEI SV: 10
FSN: UF742485940106
+GCAP: +CGSM


OK
at+creg?
+CREG: 0,1

OK
at+cmni?
ERROR
at+cnmi?
+CNMI: 1,1,0,2,0

OK
at+cpms?
+CPMS: "SM",8,20,"SM",8,20,"SM",8,20

OK
at+cmgf?
+CMGF: 0

OK

+CMTI: "SM",8
at+cmgr=8
+CMGR: 1,,30
0791447758100650040C91xxxxxxxxxxxx0000027061707405400CD4F29C0E6A97E7F3F0B90C

OK

Regards

Matt

3

BTW EM7565 and EM7511 (I only have a 65) share a code base and it is not going to be different between the carriers either as this is base functionality which has been around since the year dot.

Regards

Matt

4

Matt,

Thanks for the reply. I understand about having proprietary commands and I absolutely don’t want to use them, but here’s the problem that I’m having:

I’m simply trying to receive an SMS via PDU, that’s all.

AT+CNMI?
+CNMI: 1,1,0,2,0

OK

Alright, looks like I will receive new message notifications. Let me try receiving a message…

$QCMTI: "ME",2

What is this? I’m expecting a +CMTI

Alright, let me try to read it:

AT+CMGL
OK
AT+CMGR=2
+CMS ERROR: 321

Where’s the message?

AT+CPMS?
+CPMS: "SM",0,0,"SM",0,0,"ME",0,23

OK

It’s not in storage.

But wait… what’s this?

AT$QCPMS?
$QCPMS: "ME",3,99,"ME",3,99,"ME",3,99

OK

A different undocumented storage? And my new message is here? Let me try to read it.

AT$QCMGR=2
$QCMGR: "REC UNREAD","8455441812","20/07/16,15:45:40+00",,129,4
Test

OK

There’s my message, but how do I get it in PDU?

AT+CMGF?
+CMGF: 0

OK
AT$QCMGF=0
ERROR
AT$QCMGF=?
$QCMGF: (1)

OK

I have PDU mode set, but it’s still reading it in TEXT? Maybe I need to set the proprietary PDU mode? But I can’t, it only supports TEXT.

See what I mean. Is there no way of receiving SMS messages in PDU mode on this modem?

Am I missing something?

This is an EM7511 with the Verizon firmware SWI9X50C_01.08.04.00 (release 12).