Evaluation Type: Independent Products
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?: null
What were the biggest problems encountered?: My lack of familiarity with the MBED method of programming. I was expecting to download an IDE rahter than use an online compiler. However this has got to be one of the best methods you can use in hindsight as it is sooo easy to get the software to run on the demo board.
I have written my review and it can be downloaded from here
I hope you enjoy reading as much as I did wiritng this review.
I have learnt a bit about encoding data as a result. Cool!
Hopefully more to follow once I get my head around what to change in the MBED code.
Ok I have been playing around with the MBED online editor and have realised it does have some drawbacks.
In most IDE editors I have had experience with (only a few) there is the ability to have some interaction with the controller to get realtime values displayed.
This is really useful when trying to guage the values from a sensor or inputs.
I may be wrong but there appears to be no realtime connection between the controller and the online editor meaning you have to 'suck and see' when trying
to scale analogue inputs.
After a bit of fiddling I have the previously labelled "filter life" sensor now reading ambient light as a percentage (who knows as a percentage of what?)
It now goes up and downj with changes, still triggers the filter life alarm when it drops below the preset of 26%.
I have set hard limits of 5% and 95% for the light sensor as I found that if the signing (+ or -) have an effect on the encoding of the data to the controller.
If the sensor value drops into negative values it really stuffs up the SHA256 hashing. The controller then says the sensor is not authentic.
NB: The ambient light values I have reading on the display seem to be pretty erratic. Probably due to my programming.
Measuring ambient light and turning it into something meaningful is always a struggle.
Unless you can measure Lux using a proper tool, there is really no reference.
Even then an app designed for measuring outdoor light is going to be vastly different when measuring indoor light.
Visual light is only one component and while that may appear low, the UV or IR component may be still just as high which could suit plants or heating.
One aspect of IoT security is that many devices only send data when there is occupation, so in order to combat this the device needs to feed a constant suppy regardless of occupation.