Amasing work guys!
If anyone still has the problem with spindle speed smaller with 1 than command speed (eg: m3 s10000 will set the spindle to 9999) do the folowing in hy_vfd.c
Replace:
freq = abs((int)(*(haldata->speed_command)*hzcalc*100));
With:
freq = abs((int)(*(haldata->speed_command)*hzcalc*100));
if (freq > 0)
freq += 1;
It's a rounding problem.
Thanks
Mihai