Observations on PSM Testing with BC95-G Modem

IoT Modules LPWA Module
1

Hello,

I am working with a BC95-G modem mounted on a GSM/EVB base, conducting tests related to Power Saving Mode (PSM). Below, I detail the commands used and their execution order:

  • ATI
  • AT+CGMM
  • AT+CGDCONT=1,“IP”,“PSM_APN”
  • AT+CSCON=1
  • AT+CGATT=1
  • AT+CPSMS=1,“10100101”,“00100011”
  • AT+NPSMR=1
  • AT+CEREG=4

The output is like this:

[2025-10-22 17:01:27:202_R:] REBOOT_CAUSE_APPLICATION_AT
[2025-10-22 17:01:27:202_R:] Neul 
[2025-10-22 17:01:27:202_R:] OK
[2025-10-22 17:01:30:899_S:] ATI
[2025-10-22 17:01:30:963_R:] ATI
[2025-10-22 17:01:30:963_R:] Quectel
[2025-10-22 17:01:30:963_R:] BC95-G
[2025-10-22 17:01:30:963_R:] Revision:BC95GJBR01A05

[2025-10-22 17:01:31:026_R:] OK
[2025-10-22 17:01:32:891_S:] AT+CGMM
[2025-10-22 17:01:32:967_R:] AT+CGMM
[2025-10-22 17:01:32:967_R:] BC95GJB-02-STD

[2025-10-22 17:01:32:967_R:] OK
[2025-10-22 17:01:36:419_S:] AT+CGDCONT=1,"IP","PSM_APN"
[2025-10-22 17:01:36:518_R:] AT+CGDCONT=1,"IP","PSM_APN"
[2025-10-22 17:01:36:518_R:] OK
[2025-10-22 17:01:38:491_S:] AT+CSCON=1
[2025-10-22 17:01:38:565_R:] AT+CSCON=1
[2025-10-22 17:01:38:565_R:] OK

[2025-10-22 17:01:40:776_R:] +CSCON:1
[2025-10-22 17:01:40:916_S:] AT+CGATT=1
[2025-10-22 17:01:41:006_R:] AT+CGATT=1
[2025-10-22 17:01:41:006_R:] OK
[2025-10-22 17:01:44:523_S:] AT+CPSMS=1,,,"10100101","00100011"
[2025-10-22 17:01:44:622_R:] AT+CPSMS=1,,,"10100101","00100011"
[2025-10-22 17:01:44:622_R:] OK
[2025-10-22 17:01:50:228_S:] AT+NPSMR=1
[2025-10-22 17:01:50:320_R:] AT+NPSMR=1
[2025-10-22 17:01:50:320_R:] OK
[2025-10-22 17:01:50:699_S:] AT+CEREG=4
[2025-10-22 17:01:50:783_R:] AT+CEREG=4
[2025-10-22 17:01:50:783_R:] OK
[2025-10-22 17:01:53:899_S:] AT+CEREG?
[2025-10-22 17:01:53:972_R:] AT+CEREG?
[2025-10-22 17:01:53:972_R:] +CEREG:4,1,8150,00382224,9,,,00100011,

[2025-10-22 17:01:54:034_R:] OK
[2025-10-22 17:01:58:515_S:] AT+NUESTATS
[2025-10-22 17:01:58:583_R:] AT+NUESTATS
[2025-10-22 17:01:58:583_R:] Signal power:-1024
[2025-10-22 17:01:58:583_R:] Total power:-872
[2025-10-22 17:01:58:647_R:] TX power:210
[2025-10-22 17:01:58:647_R:] TX time:991
[2025-10-22 17:01:58:647_R:] RX time:20532
[2025-10-22 17:01:58:647_R:] Cell ID:3678756
[2025-10-22 17:01:58:708_R:] ECL:1
[2025-10-22 17:01:58:708_R:] SNR:-10
[2025-10-22 17:01:58:708_R:] EARFCN:9416
[2025-10-22 17:01:58:708_R:] PCI:95
[2025-10-22 17:01:58:708_R:] RSRQ:-145
[2025-10-22 17:01:58:708_R:] OPERATOR MODE:3
[2025-10-22 17:01:58:770_R:] CURRENT BAND:28

The modem successfully enters PSM, and the TAU and Active Time values are respected as expected.
However, I have noticed a few situations that raise questions:

  1. Using a power consumption monitoring application, a significant drop in consumption is observed when the URC +NPSMR:1 is received, indicating a correct entry into PSM. The issue is that, despite this, the modem remains responsive to AT commands, which should not happen if it were truly in a low-power state.
[2025-10-23 09:49:33:923_R:] +NPSMR:1
[2025-10-23 09:50:16:264_S:] AT}
[2025-10-23 09:50:16:335_R:] AT}
[2025-10-23 09:50:16:335_R:] ERROR
[2025-10-23 09:50:18:182_S:] AT
[2025-10-23 09:50:18:252_R:] AT
[2025-10-23 09:50:18:252_R:] OK
[2025-10-23 09:50:23:223_S:] AT+CSQ
[2025-10-23 09:50:23:309_R:] AT+CSQ
[2025-10-23 09:50:23:309_R:] +CSQ:30,99

Although the NETLIGHT and LIGHT_MOS LEDs on the GSM/EVB base do not seem relevant for these tests, the STATUS LED is. Throughout all tests, this LED remains off, even when the modem is fully operational. This could indicate a fault in the base itself, which may be indirectly affecting the modem’s behavior in PSM as described in point 1.
It was electrically verified that all LEDs are functioning correctly, so none of them are damaged or disconnected.

  1. When executing the AT+CEREG? command (previously configured with option 4), only the Active Time value is displayed. I am unsure if this is the expected behavior.
[2025-10-23 09:47:11:255_S:] AT+CEREG?
[2025-10-23 09:47:11:321_R:] AT+CEREG?
[2025-10-23 09:47:11:321_R:] +CEREG:4,1,8157,003E4B23,9,,,00100011,
  1. It has been particularly difficult to find official documentation for the BC95-G, possibly because the module has been discontinued. I would like to know if, in addition to the general AT command manual, there is a document specifically dedicated to advanced configurations (similar to the AT+QCFG commands in BG96 and BG77 modules). It is likely that I am missing a command mentioned in a manual I currently do not have access to.
  2. During the testing process, a noteworthy event occurred: it seems that an incoming call was attempted but ultimately failed. It is unclear how this functionality was triggered or how it can be disabled.
    This behavior is particularly important because receiving a call implies that the module is connected to a 3G network. However, both NB-IoT and PSM operate over 4G/LTE networks, which likely explains why the modem is unable to enter deep sleep mode.
    image
    image310×175 6.32 KB
2025-10-23 09:57:47:482_R:] OK
[2025-10-23 09:58:21:747_S:] AT+CLCC
[2025-10-23 09:58:21:855_R:] AT+CLCC
[2025-10-23 09:58:21:855_R:] ERROR
[2025-10-23 09:58:21:870_S:] AT+CLCC
[2025-10-23 09:58:21:995_R:] AT+CLCC
[2025-10-23 09:58:21:995_R:] ERROR
[2025-10-23 09:58:22:011_S:] AT+CLCC
[2025-10-23 09:58:22:121_R:] AT+CLCC
[2025-10-23 09:58:22:121_R:] ERROR
[2025-10-23 09:58:22:137_S:] AT+CLCC
[2025-10-23 09:58:22:246_R:] AT+CLCC
[2025-10-23 09:58:22:246_R:] ERROR
[2025-10-23 09:58:22:262_S:] AT+CLCC
[2025-10-23 09:58:22:372_R:] AT+CLCC
[2025-10-23 09:58:22:372_R:] ERROR
[2025-10-23 09:58:22:387_S:] AT+CLCC
[2025-10-23 09:58:22:494_R:] AT+CLCC
[2025-10-23 09:58:22:494_R:] ERROR

This is the current configuration of the modem using the command AT+NCONFIG?

[2025-10-23 09:57:46:858_R:] AT+NCONFIG? 
[2025-10-23 09:57:46:858_R:] +NCONFIG:AUTOCONNECT,TRUE
[2025-10-23 09:57:46:858_R:] +NCONFIG:CR_0354_0338_SCRAMBLING,TRUE
[2025-10-23 09:57:46:920_R:] +NCONFIG:CR_0859_SI_AVOID,TRUE
[2025-10-23 09:57:46:982_R:] +NCONFIG:COMBINE_ATTACH,FALSE
[2025-10-23 09:57:46:982_R:] +NCONFIG:CELL_RESELECTION,TRUE
[2025-10-23 09:57:47:045_R:] +NCONFIG:ENABLE_BIP,FALSE
[2025-10-23 09:57:47:045_R:] +NCONFIG:MULTITONE,TRUE
[2025-10-23 09:57:47:045_R:] +NCONFIG:NAS_SIM_POWER_SAVING_ENABLE,TRUE
[2025-10-23 09:57:47:108_R:] +NCONFIG:BARRING_RELEASE_DELAY,64
[2025-10-23 09:57:47:170_R:] +NCONFIG:RELEASE_VERSION,13
[2025-10-23 09:57:47:170_R:] +NCONFIG:RPM,FALSE
[2025-10-23 09:57:47:232_R:] +NCONFIG:SYNC_TIME_PERIOD,0
[2025-10-23 09:57:47:232_R:] +NCONFIG:IPV6_GET_PREFIX_TIME,15
[2025-10-23 09:57:47:295_R:] +NCONFIG:NB_CATEGORY,1
[2025-10-23 09:57:47:295_R:] +NCONFIG:RAI,FALSE
[2025-10-23 09:57:47:295_R:] +NCONFIG:HEAD_COMPRESS,FALSE
[2025-10-23 09:57:47:359_R:] +NCONFIG:RLF_UPDATE,FALSE
[2025-10-23 09:57:47:359_R:] +NCONFIG:CONNECTION_REESTABLISHMENT,FALSE
[2025-10-23 09:57:47:420_R:] +NCONFIG:PCO_IE_TYPE,EPCO

I appreciate in advance any guidance you can provide regarding these observations.
Best regards,

2

The BC95G has reached end of life. Do you still need to provide an answer?

3

I’m fully aware that the module has reached the end of its lifecycle. However, the previous inquiries are still useful for the tests I’m currently conducting.

My main focus is working with a newer module, the BG96. Nevertheless, I’ve encountered a few issues that I’m already addressing with the support team in my region.

By chance, I found a BC95-G module in the lab, which was used in earlier projects. I decided to replicate the same tests with this module to compare the behavior of both devices under identical conditions.

To summarize, I’m not developing a prototype, a concept project, or anything remotely productive. The sole purpose of these tests is research to ensure that the PSM functionality works correctly at a national level in my country.
So if I get an answer to the above questions it would be very helpful for the current development.

4

I have sent you the log capture tool and the guidance document. I need you to capture the logs for analysis.

5

I’m almost ready to retrieve the logs; however, I need to obtain the “messages.xml” file.
According to another forum, this depends on the firmware installed on the module. Currently, the module has the FW BC95GJBR01A05, as indicated by the ATI command shown in the initial post of this forum. Is it possible to obtain this .xml file?

1
1482×320 27.1 KB

P.S. I also found a “message.xml” file in another forum, but it’s intended for version BC95GJBR01A07. If it’s not possible to obtain the .xml file for my version, would it be possible to use the one from this newer version instead?
Thanks you in advance

6

BC95GJBR01A04.zip (1.0 MB)

7

Attached is the export file
The procedure followed was:

  1. Connect to the network.
  2. Negotiate PSM (Power Saving Mode) timers.
  3. Wait for the modem to enter PSM.
  4. Execute AT commands to demonstrate that the modem remains responsive even while in PSM (after receiving the URC +NPSMR).
    BC95-G_logs_v2.Zip (449.8 KB)
    Thanks in advance