BLE characteristic advertsiing
I'm advertising temperature through BLE, is i wish to consume this value, do i need to connect to the BLE to read the characteristic? Im using BLE Scanner on my android and have to connect to the Lopy to read the characteristic, is this what i need to do with a BLE to mqtt server?
i have lopy4 that advertisers temperature data every 30minutes and want to consume this data when it's available. At the moment, I'm creating another lopy just to continually scanner for this characteristic and then forward it though mqtt. Would tyhis be the correct way to achieve this?
do i need to connect to the BLE to read the characteristic?
Of course yes, service and characteristic can be read/write only after a connect.
is this what i need to do with a BLE to mqtt server?
It's depend only of what you want to do, if you have only some bytes of data, you can advertise it in your lopy manufacturer data (in your device stop advertising, change data and restart advertising) and then don't need to connect to lopy to have your data. If you have more than 21 bytes then you have to connect to read the characteristic beacause it's not fit in advertising maximal length.