I am writing to seek assistance with a challenging issue I've encountered in a project involving the nRF9160 module and Truphone eSIM for a pet tracker application.
I have recently come across a behavior that appears to be related to Power Saving Mode (PSM) settings, specifically with Truphone SIM (I have eSIMs and a normal SIM card). After further investigation, I have identified that the root cause of the issue is likely due to my experimentation with PSM settings.
Here are some key points regarding the situation:
- Messages sent from the nRF9160 Development Kit (DK) to our MQTT server are delivered promptly and reliably.
- However, when attempting to send messages from the MQTT server to the DK, the process is sporadic, especially when the modem enters Idle mode (as indicated by +CSCON: 0 and RRC mode: Idle).
- It's important to note that this behavior is not observed when using an iBases SIM card with an identical hardware and firmware configuration.
- During my testing phase, I inadvertently altered the PSM settings for a specific Truphone eSIM, probably leading to the TAU value of 10800 and an Active time of -1.
- The firmware and settings are uniform for both the Truphone and iBasis SIM card configurations.
- PSM has been explicitly disabled using the lte_lc_psm_req(false) function in my firmware.
- The PSM parameter update for the Truphone SIM card that consistently exhibits the issue is: TAU:10800, Active time: -1.
- I have also checked another Truphone SIM card, which now shows the expected PSM parameter update of: TAU: 3240, Active time: -1.
- I have also checked another iBasis SIM card, which now shows the expected PSM parameter update of: TAU: 3240, Active time: -1.
PM is currently off (CONFIG_PM=n), int modem_init(void) {
int err;
//disable PSM
lte_lc_psm_req(false);
lte_lc_edrx_req(false);
//lte init
err = lte_lc_init();
if (err) {
printk("LTE modem INIT ERROR.\n");
return -EINVAL;
}
lte_lc_register_handler(lte_handler);
printk("- modem_init completed\n");
return err;
}
If it is because of PSM settings then how can I revert it to the default/initial state?
I am seeking your expert advice and guidance to help me address this challenge. Specifically, I am interested in understanding how my experimentation with PSM settings could be affecting the behavior of the Truphone eSIM. Any insights, recommendations, or suggestions for troubleshooting would be greatly appreciated.
If there is any additional information, data logs, or specific tests that you would recommend to better diagnose the issue, please let me know, and I will be more than happy to provide them.
Modem trace: trace-2023-08-17T21-50-03.572Z.mtrace.zip
Thank you for your time and consideration.
Best regards,
Sergii Skorostetskyi
