I have 15 sonoff dw2 door window sensors.
They only report when a door is open, not when it closes.
Question 1, is it possible to amend the firmware to make it trigger on both open and close, if so how?
Question 2, these are useless to me in their current state and I’d be happy to sell them on if someone has a use for them?
Ooooor, can anyone think of a use case for these sensors?
Thanks
Colin
Does it report open continually or just when opened?
Expire timer wouldxwork on former
only when the reed sensor detects the opening of the door, so just a single message.
Expire timer might work, but rarely do i want to know when a door is only open, i usually want to know when it’s closed also
They only show if open because they are usually set to an alarm system and therefore only need to know if the door or window has been opened.
I bought 10 of those by mistake and haven’t even got them out of the packaging.
I wanted to order the Sonoff ZibBee SNZB-04 which does open and closed and also battery status. I clicked the wrong picture. 
I have 15 unopened here, with a further 5 opened 