Hey Railroader!
As mentioned I can make it work with DRV8825 drivers and I gues A4988 also work as these drivers both are what the cnc shield is made for. However, the A4988 is even louder than the DRV8825. If you wtach this video I hope it is clear why I wanted to use stealthchop2 for a wall clock in my leving room xD
A4988 VS TMC2208 Noise comparison
I choose the 2209 instead of 2208 because it semed to be a cheaper and newer version of the 2208 driver.
I do not know the 6650 drivers and cannot find them. Do you have a link?
I could have chosen the TMC2100 as they are STEP/DIR/EN only boards like the A4988 and DRV8825. However, they only use stealthcop and not stealtchop2 wich is even quieter. And it was my understanding from both the datasheet and variuos websides that the 2209 would also work in this "legacy" mode as seen here and on page 4 and more.
From 2209 datasheet
I may buy some TMC2100's, but its gonna take weeks before I get them. And I would really like to understand why the 2209's are not working. I really do not see why they wouldn't. It is most likely a simple stupid mistake somewhere as I am no electronics/software expert. I am just a mechanical engineer who likes to make things move..
But thanks for your input!