I've got an application that needs a reasonably fast, and very stable clock to measure the frequency of an incoming square wave up to a few kHz.
I'm not getting a stable reading using the internal clock, so I dug up a couple of crystals: a 2MHZ and a 16MHz crystal and now I'm wondering how to make this work? Can I use the 16M?
The two ICS control registers are very confusing, can anybody explain any of this for me?
In particular: What does the High Gain option do? Do I need high or low frequency range?
It sounds like using anything but FBELP limits my external source to around 4.6MHz to keep a 36kHz FLL...
Any help is appreciated, thanks!