ATOM-DTU-NB-IoT - modem does not respond anymore

erazor

Update for anybody who's reading this.

My previous assumption that the reset-button kills the modem seems incorrect.

I've had another two devices and carefully did not use the reset-button at all but these modules also stopped working.

erazor

@forairaaaaa you can find my code here:
https://github.com/erazor83/nb_dtu_reset_issue/

Felix22

i can not use this code, Error:

In file included from N:.....\nb_dtu_reset_issue-main\src\main\main.ino:21:
c:\Users\fb\Documents\Arduino\libraries\TinyGSM\src/TinyGsmClient.h:118:2: error: #error "Please define GSM modem model"
#error "Please define GSM modem model"
^~~~~
exit status 1

Compilation error: exit status 1

felmue

Hello @Felix22

please do not use the nb_dtu_reset_issue code - it was meant to debug an issue and can change the baudrate of the SIM7020 modem.

Thanks
Felix

johseffer

@felmue you solve that? Happened with me today, i think after i send a "AT&F" to factory reset the configurations, so now my module stop reply to at commands

felmue

Hello @johseffer

yes. See here.

Thanks
Felix

fkarner

Hello,

I'm working as well with the above mentioned hardware (7020G modem). For a while the program worked fine. Unfortunately since some time the modem does not respond anymore.

The example MQTT code given here does not work (no errors). I think I'm using the needed libraries, so I would not expect errors coming from there. The here already mentioned way to solve the problem by changing the baudrate was not successfull - still silence.

The Serial Monitor Output indicates that the initialisation is not possible:
21:23:10.998 -> waiting....1067s
21:23:26.485 -> waiting....1082s
21:23:41.922 -> waiting....1098s
21:23:57.420 -> waiting....1113s
21:24:12.866 -> waiting....1129s
21:24:28.348 -> waiting....1144s
21:24:43.793 -> waiting....1159s
21:24:59.276 -> waiting....1175s

so the M5Atom is still stuck here:

 while (!modem.init()) {
        log("waiting...." + String((millis() - start) / 1000) + "s");
    };

I really don't know how to solve this problem. Since I'm not an expert in programming I would be thankful if someone could help me out with a code to send simple AT-Commands via the Serial Input.

Thanks in advance
flori

felmue

Hello @fkarner

hmm, since you already tried changing the modem baudrate I am at a loss what might have gone wrong.

Maybe my serial pass-through example can shed some light onto this issue?

Thanks
Felix

fkarner

@felmue said in ATOM-DTU-NB-IoT - modem does not respond anymore:

hmm, since you already tried changing the modem baudrate I am at a loss what might have gone wrong.

Hi Felix,

thank you very much for your answer and the code example. I can upload the code, without errors. The Atom stops here:

19:19:49.162 -> ets Jun 8 2016 00:22:57
19:19:49.162 ->
19:19:49.162 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
19:19:49.162 -> configsip: 188777542, SPIWP:0xee
19:19:49.162 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
19:19:49.162 -> mode:DIO, clock div:1
19:19:49.162 -> load:0x3fff0030,len:1344
19:19:49.162 -> load:0x40078000,len:13964
19:19:49.162 -> load:0x40080400,len:3600
19:19:49.162 -> entry 0x400805f0
19:19:51.594 -> Start SIM7020 passthrough test

Unfortunately I do not get answer thru the serial monitor... I've tried:
AT+CEER=?, AT+CGMI=?, AT+CFUN=1. No response... By the way the modem LED's show acitivity red is on, blue flashes with ~.5Hz....

After that I reinstalled Arduino IDE. Now there are only the M5Stack Boards and the Arduino Boards listed. As Libraries I installed only the M5Unified and the M5GFX. I'm clueless. What could I try next?

Update: I've tried another 7020G modem. That one answers....

*19:43:58.890 -> ets Jun 8 2016 00:22:57
19:43:58.890 ->
19:43:58.890 -> rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
19:43:58.922 -> configsip: 188777542, SPIWP:0xee
19:43:58.922 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
19:43:58.922 -> mode:DIO, clock div:1
19:43:58.922 -> load:0x3fff0030,len:1344
19:43:58.922 -> load:0x40078000,len:13964
19:43:58.922 -> load:0x40080400,len:3600
19:43:58.922 -> entry 0x400805f0
19:44:01.378 -> Start SIM7020 passthrough test
19:44:04.165 -> AT+CEER=?

19:44:04.197 -> +CEER: (0,1)
19:44:04.197 ->
19:44:04.197 -> OK
19:44:14.518 -> AT+CGMI=?*

Thanks, flori

felmue

Hello @fkarner

thank you for the update. So it's confirmed something's wrong with the first SIM7020G. I still suspect the baudrate got changed somehow, especially since you are writing that the LEDs behave normally.

Thanks
Felix

fkarner

Hi @felmue

Yes I agree, there must be something wrong with this module. I will investigate that later... First priority is to set up one DTU NB IOT module.

Unfortunately also with the working modem I get errors using the MQTT code example:

12:37:55.848 -> Initializing modem...
12:37:55.848 -> [ 62][E][esp32-hal-gpio.c:102] __pinMode(): Invalid pin selected
12:37:55.848 -> E (61) gpio: gpio_set_level(227): GPIO output gpio_num error
12:37:56.138 -> E (364) gpio: gpio_set_level(227): GPIO output gpio_num error

May they come from the reistallation of Arduino IDE?
Here are my compiling settings:

I found the error code here. For sure there must be something wrong with the serial communication.... Strange....

flori