First of all I'm a BLE novice, so sorry if I'm asking obvious questions. I've built a home project where a battery powered mcu listens for requests over wifi and drives a couple of solid state relays. It works but power consumption is being an issue, so I'm thinking about moving from wifi to BLE, in particular an nrf51822.
I think my use case is different from the typical BLE application where a low powered sensor is mainly deep sleeping and otherwise broadcasting a temperature value with a payload when advertising. In my case, I need the advertiser to react to a request from central (where power is not a problem) within 1-1.5 seconds, about 5-10 times a day. I till now figured two possibilities, but I ask you to tell me if it's feasable and which one you think is better.
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Advertise every 1s and have the central ignore it until there is a request pending on the application server side. At this point, initiate a connection at the first advertisement received, send in the request (a few bytes) and close the connection.
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Keep the connection open using a connInterval of 1s and send the request as soon as possible
Which method should consume less power?
Considering that the devices are always under 5 meters apart and there should be no issue in keeping a connection open, can you give me a hint on the avg power consumption when waiting for a trigger (e.g. assuming 0ms data processing)? I understand I should give other info to have a figure, but what I need at the moment is a broad estimation based on experience (that I don't have).
Thanks for you input.
