All my devices are on 1.1.15 3xTbeam0.7 and 1x heltec Phone app version 1.1.02 . I have the Heltec connected to serial port for debugging. And One Tbeam running off battery to test functionality.
Clicking from Heltec to None in the BLE on the Phone app. If the Heltec goes to sleep. Then it is none discoverable until it does a periodic wake, Only spotted by the activity on my serial monitor. I conclude from this that scan for devices on the app is not waking the modules.
The data sheet suggest that BLE is switched off in all forms of sleep. I am guessing this is where the issue is. Not sure if there is a coding method to directly communicate with the BLE device to put into low power mode and wake to full power Via ULP processor coding mode when activity has been seen. This direct coding of devices would also have to be used for the other peripherals such as WiFi and main core to sleep. Rather than use the blanket esp32 Sleep(); . Not seen any example code of this on the internet, so quite possibly can’t be done
Other issue found when i pair with the Tbeam. Sending a packet to the Heltec. The Heltec wakes , But If it is badly formed packet. The Heltec just goes back to sleep rather respond with I am here but did not receive packet correctly.