Check if bluetooth device is connected or not

hi , i'm working in project to collect data from sensors with bluetooth (data : json) , and i want to get status of bluetooth device is connected or not , i have data gathered from sensors or not .. the data json still the same if i disconnect if device so can't judge if bluetooth connected or not .

What node are you using? What does your flow look like?

i'm using serial port of node red

And what module do you have connect to the serial port?

module bluetooth HC-05 , i'm alredy connected to it and i have the data