I bought an STM32 evaluation board today. And a bunch of level shifters (needed to convert the 3.3 volt signals to 5 volts).
This is the small beginning of the new HAWK. I've talked about this before. But let me recap for those who missed it or are new to the group.
The goal is to replace both the 80C85 CPU and the MSM5232 tone generator in the Poly/EX-800 with an STM32 processor.
Then rewrite the code entirely so that we get:
1) Eight independent voices each with...
2) Independent low pass and resonant filters as close to NJM2069 as we can program.
3) Independent frequency modulators.
4) Multiple waveforms (not sure how many or even how they will be generated but square, saw, triangle, PCM, phase shifting, cross modulation etc are all under consideration).
5) MSM5232 emulation (exactly the same operation and characteristics that Poly already has in its TG).
6) LCD display option 16x2 back lit (while also keeping original display and keypanel).
7) keep all other Poly/Hawk functions.
8) add multiple input/output options for expansion.
9) An effects stage (and reduce noise).
As I've said before, I have so much other work going on that I really have no idea how long this is going to take. But I am at least in the early stages of actually doing it. Which is still better than not at all.
And the big question still remains, do I create a brand new drop in replacement main board (and move the NJM2069 over to it)?
/Mike