TemperatureSensorBasedonLSCDoorSensor
Besides the generic LSC Door and PIR sensor with ESPNOW, i'm also working on an experimental sensor mod.
First setup is a temperature/humidity sensor based on the doorsensor.
As the ESP has no control over the power source and is completely powered off in idle state, we can't use normal deepsleep approach. Benefit of the LCS doorsensor is that it includes a power controlled step-up converter to power the ESP with a clean 3.3 Volts even if battery has a much lower voltage.
So we need a way to periodically boot the device. In theory, i guess it should be possible to reprogram the onboard MCU but that's beyond my skills and would likely need a lot of reverse engineering.
Instead, i dug up one of my old friends: the ATTiny85
I had programmed these chips before and also found useful code on the letscontrolit repository to turn the ATTiny into a programmable I2C slave that can do things like boot the sensor, read battery voltage, additional analog/digital ports.
This is step one, adding to ATTiny85 to the doorsensor in a way that it will stil fit into the original case:
It has been working for several days and seems stable. Not shown in the picture above is the SI7021 sensor that's now running for a day and producing charts in Domoticz.