I have your ESP32 ebook and I am working through the LORA sections. I would like to send a sensor reading from the sender to a receiver (Heltec Lora oled v2). The sender will be on solar battery and in deep sleep most of the time. Can you help with code to have sender wake up from Deep Sleep every 2 hours, collect reading and send to receiver unit, wait for response then go back to sleep? I have sender working with sensor and sending readings to receiver, but not going back to sleep.
Have you taken a look at the Additional Projects in the ESP32 eBook?
We have a LoRa project that is exactly what you are looking for. See Module 12: https://rntlab.com/module-12/esp32-lora-sender-part-2/
Or go to the eBook page: 598
Let me know if this helps.