Description
My OVMS3.3 modem occasionally drops to 2G/GSM after staying connected for a period of time (approx. half a day); additionally, if AT+CNMP=38 is set (to force LTE only), it will instead not be able to connect to any network at all.
For context: the telco I'm using only has GSM and LTE, no UMTS. However, RSSI on GSM is typically much poorer than on LTE (approx -98dBm vs -60dBm), so I'd like to stay on LTE where possible.
Weirdly enough, a modem reset (with AT+CRESET) or module reset is sufficient to get it back onto LTE again, every single time.
Still haven't figured out why this is the case, but I'm wondering if this is a known issue in the modem firmware or something? Or perhaps my telco is messing with me? Though the latter doesn't seem that likely, given that a reset gets me back onto LTE without fail.
For now, I'll probably have to write a script to automatically reset the modem if this happens -- AT+CNMP=38 + network/reboot.no.ip doesn't help here, since it only reboots the module if m.net.good.sq is true