SIM7070G Modem Power-on Failure

[tadenham]

I have several weather stations deployed with SIM7070G boards and all have had this same issue at some point. These weather stations transmit regularly at 15-minute intervals, powering on the modem and then shutting down again when the transmission is complete. They will all operate normally anywhere from several days to several months, then suddenly the modem will fail to start. This can be verified by the STATUS and NETLIGHT LEDs not turning on when the modem is supposed to be turned on. This drains the battery very quickly as the ESP32 will wait from a response from the modem even though it is not powered on, preventing the board from going into deep sleep for a while. I can also confirm that the ESP32 still functions normally throughout this as it continues to write the data to the SD card when the transmission is unsuccessful.

The boards have never recovered from this condition, the modem will fail to power on indefinitely after this point. The modem will only operate normally once again when battery power is completely removed and the board is rebooted. This has become a major issue as these stations are located in difficult to access remote locations.

I have a few other stations with SIM7600 boards and they have operated for nearly a year so far without issue.

[baldvinhansson]

I'm sorry I don't have a solution to your problem, but want to ask if you've been able to use SIM7070G for transferring data over TCP connected to an LTE network with any consistency and reliability? And if so, would you be willing to share any or all of the relevant code?

The reason I ask is that I've not been able to do this at all and I've raised an issue here on github for this a while back and emailed LILYGO and I get no replies or answers anywhere. I'm able to do this fine on SIM7000G but SIM7070G starts out ok but after a few seconds it simply will not receive any data from the remote end/server anymore and the connection stops.

Thank you for considering this and sorry I don't have a solution at the moment to your original issue.

[tadenham]

Although I now use UDP to send data, I used to use MQTT which uses TCP. I didn't have any issues other the occasional dropped connection due to poor service, but I switched to UDP because of the lower overhead. I also added an acknowlegment from the server so that all data has guaranteed delivery.

I haven't used the SIM7000G so can't say if they behave any differently but as far as I know the AT command set is the same. I don't use any external libraries since I write the code exclusively in ESP-IDF. You might not find the following useful if you're using the libraries, but the code for both MQTT and UDP connections is in there. Much of the code is weather station stuff unrelated to the actual transmission of data.

https://github.com/tadenham/Cellular-AWS

[baldvinhansson]

Thank you for the prompt and useful answer. I will keep an eye out for potential solutions to the issue you originally described.

[Nadeem-Ullah]

I have several weather stations deployed with SIM7070G boards and all have had this same issue at some point. These weather stations transmit regularly at 15-minute intervals, powering on the modem and then shutting down again when the transmission is complete. They will all operate normally anywhere from several days to several months, then suddenly the modem will fail to start. This can be verified by the STATUS and NETLIGHT LEDs not turning on when the modem is supposed to be turned on. This drains the battery very quickly as the ESP32 will wait for a response from the modem even though it is not powered on, preventing the board from going into deep sleep for a while. I can also confirm that the ESP32 still functions normally throughout this as it continues to write the data to the SD card when the transmission is unsuccessful.

The boards have never recovered from this condition, the modem will fail to power on indefinitely after this point. The modem will only operate normally once again when battery power is completely removed and the board is rebooted. This has become a major issue as these stations are located in difficult-to-access remote locations.

I have a few other stations with SIM7600 boards and they have operated for nearly a year so far without issue.

Hi: @tadenham

I have had the same issue from last month until now, and the GSM module shuts down automatically after a day or so.
I wrote a Fall-back mechanism script using C++ that reads the USB device status to detect whether the modem is connected or not. Then, it checks for GSM modem detection and, lastly, for network availability and connectivity. After all, the script sends a ping command to transmit three packets each after two seconds and tests whether the network response is correct or not.

If the ping succeeds and the packets receive back then the loop runs continuously and if the ping throughs an error then log_file is red and checks the error and take action accordingly.

But still the modem goas power-down after a day or so,

What may be the issue?

looking for your help.

NOTE I'm connecting USB GSM modem (SIM7070G) with RaspberryPi-4 (CM-4) on my custom board and the connection are all set correctly.

Thanks