I'd already had a look at the datasheet for the chip so new it should be fairly straight forward. So I plugged the thing into my Matrix Multimedia PIC prototyping system and wrote a few routines to try it out.
I do most of my PIC development in Assembler because I'm an old fart! Also if my evil plans were to work out I'd need to have the code running as quick as possible to allow me to re-program the DDS chip about 20,000 times a second...this to allow it to do FM and scanning functions.
Within a few hours I had the thing up and running in a fairly simple setup...it used an old MS mouse as a "rotary encoder" for tuning and I could make it tune from 0-60MHz though not very comfortably. Also a quick and dirty frequency display on an LCD. This was the most challenging bit of PIC programming I've done - lots of 32bit mathematics but there are lots of great resources on the internet to help!
With the addition of an NE602 chip and a few bits and bobs I had a nice radio that I could use as a direct conversion receiver...not the greatest radio in the world but it worked!
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