I have the SIM7080G module: https://shop.m5stack.com/products/sim7080g-cat-m-nb-iot-unit
I'm using the TinyGSM lib to interface with the module. There are a couple of issues I've encountered:
Speed: downloading the google logo (~4KB) over https take 7 - 12 seconds. I've tested the SIM card from a phone and it's 1MB/s download and upload. Downloading from http was equally slow, so doesn't look like to be encryption/compute bound. What can I do to make this a bit faster?
When I make repeated HTTP calls in a loop for testing, the device would freeze or stop responding after a random amount of time (minutes). When I reboot the CPU (ESP32) sometime it would recover, sometimes not. Also when power is unplugged, sometimes the module would go into a state where it would not respond AT commands at all. I would have to power cycle the module, sometimes more than once, to get it to accept AT commands again. Is this expected and is there a reliable way to recover from this?