Hi have noticed that if the imp goes out of WiFi range or the router is turned off, the imp doesn’t detect the loss of association, or the LED doesn’t reflect that, because it still blinks green. Also, the imp doesn’t seem to attempt to re-associate if the router is turned on after the imp, as indicated by the the LED blinking red even after the router has been turned on.
Currently, wifi disassociation does not cause the LED to go red; this is a known issue and will be fixed.
If the router is turned on after the imp, the imp should try for a minute to connect then give up and sleep for 9 minutes, then the cycle repeats.
In any case, the WiFI range is impressive.
Even with the current firmware, the imp notices that Wifi has gone away as soon as it tries to send anything. If you’re testing Wifi range, you could use the “ticktock” public firmware, which sends all the time and so should notice Wifi dropping out straight away.