Hi @kennethlimcp / @mohit,
I have been doing my long term testing with the shield which is going fine - I can get readings for days without a problem.
Now I want to test in different rooms and unplug the USB which I have not been doing due to the last time I tried this it resulted in :
I cannot get the shield to work when I disconnect USB power from the core. It could be a power issue.
The PSU I am using is 12VDC 2.0A (+ve in center)
USB plugged in
Everything works fine
Breathing cyan on spark
Shield blue LED solid
Unplug the USB
Core stops what it was doing (in a stage where shield LED is flashing)
Spark LED goes yellow and flickers very fast
Shield blue LED flickers very fast
Something whistles in vicinity of grove ports (spark/PR326/6X)