Thanks to Rory encouragements, I throw the idea of the new project into the pool!
It will be a 5 oscillators Cabbage 2 FM synth based on poscil opcodes.
@Oeyvind csound page are very inspiring.
Should you like to provide feedback, advice, criticism, you are welcome. It is likely your help will be needed.
There will be a github project page for it.
First question to anyone who can have a look at the code (around lines 571 -595) and at the little UDO called FM, is the following :
In the code, are the different stages of oscillators correctly chained according to the figures shown in the synth interface ( parallel, serie, mixed, ..).
Here is the very early stage ( it already makes sound) FM_me.zip (375.4 KB)