Yes you can scale down to read the analogue inputs, the east straight forward way is to use a voltage devider to scale down the voltage.
However there are a few things you need to be aware of.... here are the ones I know of and would consider if I was doing it, maybe others can add the ones I may have missed.
- Do you have a way of protecting the Axo from a voltage spike higher then 3.3 volts hitting the analogue input ? This may not hurt the Axo, but would definately kill the analogue input and make it unusable.
- Where is the voltage source to be scaled down comming from ? If the power from the source and the Axo are connected to the same power source, this would be OK, but if it is a different power source, the voltage going into the axo needs to be isolated from the source origin, allot like how Midi uses an opto coupler to isolate two midi devices, but I am not aware of opto couplers being used for Analogue signals so you may need to find a different way to to get the signal through, for me, so far I have found solutions by sharing the same power supply to cover all my needs which is in line with have a complete seperate standalone system for the Axo.
I know I have only mentioned two things, dealing with analogue signals there may be a few more, but hopefully this will get you in the right direction.