EM7455 stuck offline

IoT Modules MC/EM Series
1

Hello,
we got 20 pcs of EM7455 module all are working except one that is consistenly stuck offline.
I’ve searched a bit but still not found a reason for weird behaviour.

at!gstatus?
!GSTATUS:
Current Time: 1409 Temperature: 28
Reset Counter: 1 Mode: OFFLINE
System mode: LTE PS state: Not attached
LTE band: No band LTE bw: 1.4 MHz
LTE Rx chan: 0 LTE Tx chan: 4294967295
LTE CA state: NOT ASSIGNED
EMM state: NULL —
RRC state: RRC Idle
IMS reg state: No Srv

PCC RxM RSSI: 0 RSRP (dBm): 0
PCC RxD RSSI: 0 RSRP (dBm): 0
Tx Power: 0 TAC: 0000 (0)
RSRQ (dB): 0.0 Cell ID: 00000000 (0)
SINR (dB): 0

OK

at!pcinfo?
State: Offline
LPM voters - Temp:0, Volt:0, User:0, W_DISABLE:0, IMSWITCH:0, BIOS:0, LWM2M:0, OMADM:0, FOTA:0
LPM persistence - None

OK

Any help or hint is greatly appreciated.

Thanks,

2

Hi @micheletti.marco

Which firmware are you using?
Can you try to download the latest firmware to module?

You can get the latest firmware in this link:
https://source.sierrawireless.com/resources/airprime/minicard/74xx/airprime-em_mc74xx-approved-fw-packages/#sthash.eIXAQkd1.dpbs

There are a few scenarios where the module will show up as offline:

  1. Host is putting the module OFFLINE via AT or QMI commands.
  2. Windows FDT puts the module OFFLINE and then downloads FW. If the module gets stuck and doesn’t reset, AT port will show OFFLINE.
  3. RF Calibration is missing.

Please provide following AT log:

ATI
AT!ENTERCND=“A710”
AT!IMPREF?
AT!IMAGE?
AT!GSTATUS?
AT!NVBACKUP?
AT!PCINFO?
AT!SKU?
AT!PRIID?
AT!CALID?
AT!CALINFO?
AT!USBCOMP?
AT!FLOG?

Please help to mark “Solution” if your question is answered.

3

Hi Donald,
Thanks for kind reply.

We are testing all modules on a Ubuntu 16 machine with ModemManager closed and disabled. Therefor there should not be any other entity to send AT commands.

All modules received have release SWI9X30C_02.24.05.06 r7040 CARMD-EV-FRMWR2 2017/05/19 06:23:09.

We tried to flash latest firmware SWI9X30C_02.32.11.00 002.064_000 but still not working. After that we revert to original firmware and after an AT!RMARESET=1 finally we got module online.

Yet I’m not clear why update to latest FW didn’t change offline condition while revert to old one did.

Anyway please find below list of reply from AT commands:

ati
Manufacturer: Sierra Wireless, Incorporated
Model: EM7455
Revision: SWI9X30C_02.24.05.06 r7040 CARMD-EV-FRMWR2 2017/05/19 06:23:09
MEID: XXXXXXXXXXXXXXXXX
ESN: XXXXXXXXXXX, XXXXXX
IMEI: XXXXXXXXXXX
IMEI SV: 12
FSN: XXXXXXXXX
+GCAP: +CGSM

OK

AT!ENTERCND=“A710”
OK

AT!IMPREF?
!IMPREF:
preferred fw version: 02.24.05.06
preferred carrier name: GENERIC
preferred config name: GENERIC_002.026_000
current fw version: 02.24.05.06
current carrier name: GENERIC
current config name: GENERIC_002.026_000

OK

AT!IMAGE?
TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
FW 1 EMPTY 0 0 0
FW 2 EMPTY 0 0 0
FW 3 EMPTY 0 0 0
FW 4 EMPTY 0 0 0
Max FW images: 4
Active FW image is at slot 255

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
PRI FF GOOD 0 0 0 002.027_000 02.24.05.06_ATT
PRI FF GOOD 0 0 0 002.026_000 02.24.05.06_GENERIC
PRI FF GOOD 0 0 0 002.022_000 02.24.03.00_SPRINT
PRI FF GOOD 0 0 0 001.000_000 00.00.00.00_OEMPRI918
PRI FF GOOD 0 0 0 002.035_000 02.24.05.06_VERIZON
Max PRI images: 50

OK

AT!GSTATUS?
!GSTATUS:
Current Time: 888 Temperature: 39
Reset Counter: 1 Mode: ONLINE
System mode: LTE PS state: Not attached
LTE band: No band LTE bw: 1.4 MHz
LTE Rx chan: 0 LTE Tx chan: 4294967295
LTE CA state: ACTIVE LTE Scell band:No band
LTE Scell bw:Unknown LTE Scell chan:0
EMM state: Deregistered Attach Needed
RRC state: RRC Idle
IMS reg state: No Srv

PCC RxM RSSI: 0 RSRP (dBm): 0
PCC RxD RSSI: 0 RSRP (dBm): 0
SCC RxM RSSI: 0 RSRP (dBm): 0
SCC RxD RSSI: 0 RSRP (dBm): 0
Tx Power: 0 TAC: 6572 (25970)
RSRQ (dB): -2082.1 Cell ID: 02164C24 (35015716)
SINR (dB): 0

OK

AT!NVBACKUP?
!NVBACKUP:
0 Factory
1 Provision

OK

AT!PCINFO?
State: Online
LPM voters - Temp:0, Volt:0, User:0, W_DISABLE:0, IMSWITCH:0, BIOS:0, LWM2M:0, OMADM:0, FOTA:0
LPM persistence - None

OK

AT!SKU?
SKU: 1103780

OK

AT!PRIID?
PRI Part Number: 9907721
Revision: 001.000
Customer: Generic-M2M

Carrier PRI: 9999999_9904594_SWI9X30C_02.24.05.06_00_ATT_002.027_000
Carrier PRI: 9999999_9904609_SWI9X30C_02.24.05.06_00_GENERIC_002.026_000
Carrier PRI: 9999999_9904779_SWI9X30C_02.24.03.00_00_SPRINT_002.022_000
Carrier PRI: INTERNAL_9901234_EM7455_00.00.00.00_00_OEMPRI918_001.000_000
Carrier PRI: 9999999_9904780_SWI9X30C_02.24.05.06_00_VERIZON_002.035_000

OK

AT!CALID?
Calibration Information:
Station ID: 902_CAL_L_32
Date: 09/09/2019
Software version: R4-0-8
Configuration version: 4.07

OK

AT!CALINFO?
SWI9X30C_02.11.03.22 r6782 CARMD-EV-FRMWR2 2016/08/24 15:18:59

OK

AT!USBCOMP?
Config Index: 1
Config Type: 1 (Generic)
Interface bitmask: 0000050D (diag,nmea,modem,rmnet0,rmnet1)

OK

4

Hi @micheletti.marco

I am happy to hear your module has online now.
Maybe you have some settings on the module that put the module in OFFLINE.

When you enter AT! RMARESET = 1, It will restore device to the specified (configuration)
= 1—“Provision” (Sierra-provisioned SKU configuration).

Please help to mark “Solution” if your question is answered. So the community could easily find the solution for their problems.

5

Hi Donald,
need to say that AT! RMARESET = 1 has been issued several times even before sw upgrade and downgrade. That was our first action for this module when we saw it was stuck offline.

Another point,
AT!IMAGE?
TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
FW 1 EMPTY 0 0 0
FW 2 EMPTY 0 0 0
FW 3 EMPTY 0 0 0
FW 4 EMPTY 0 0 0
Max FW images: 4
Active FW image is at slot 255

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
PRI FF GOOD 0 0 0 002.027_000 02.24.05.06_ATT
PRI FF GOOD 0 0 0 002.026_000 02.24.05.06_GENERIC
PRI FF GOOD 0 0 0 002.022_000 02.24.03.00_SPRINT
PRI FF GOOD 0 0 0 001.000_000 00.00.00.00_OEMPRI918
PRI FF GOOD 0 0 0 002.035_000 02.24.05.06_VERIZON
Max PRI images: 50

OK

shouldn’t be listed image 02.24.05.06 and why Active FW image is at slot 255?
see same command from a working module:

at!image?
TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
FW 1 GOOD 2 0 0 ?? 02.24.05.06?
FW 2 GOOD 1 0 0 ?? 02.24.03.00?
FW 3 EMPTY 0 0 0
FW 4 EMPTY 0 0 0
Max FW images: 4
Active FW image is at slot 1

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
PRI FF GOOD 0 0 0 002.027_000 02.24.05.06_ATT
PRI FF GOOD 0 0 0 002.026_000 02.24.05.06_GENERIC
PRI FF GOOD 0 0 0 002.022_000 02.24.03.00_SPRINT
PRI FF GOOD 0 0 0 001.000_000 00.00.00.00_OEMPRI918
PRI FF GOOD 0 0 0 002.035_000 02.24.05.06_VERIZON
Max PRI images: 50

OK

Thanks,
Regards,

6

Hi micheletti.marco,

These images are empty in this module. It can be deleted all stored image files.
Please contact your reseller or distributor directly for technical support in this case. Then you can provide DM and AT log files for further investigation.

The AT!IMAGE and AT!IMPREF commands are explained in the Image Switching M2M Developers Guide_r2.pdf.
You can get this document at here:
https://source.sierrawireless.com/resources/airprime/software/image-switching-m2m-developers-guide_r2/#sthash.7dlUJS9H.dpbs

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