@pinae I don’t understand the question- Can you move this to a new thread with more details?
I formulated the question with other words here: False positive stall detection with Farmduino 1.4 and TMC2208
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Thank you for the continued feedback that the StealthChop feature is important. Our firmware developer is working to resolve a known bug in the Genesis firmware this week, and then StealthChop is next on the firmware priority list.
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Cool! Thanks! I think that will make many users happy. 
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Amazing 
Any rough estimate when the StealthChop feature could be released (2 weeks, 1 month, 2 month, …) ?
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Not yet, but once the outstanding bug is resolved I should have an update on the StealthChop timing. Stay tuned to #announcements 
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I did a lot of testing with a Farmduino 1.4 and different stepper drivers:
- In my eyes still the best option for a quiet bot are the TMC2208 mentioned here. You can’t jumper them for full step operation but you can set the jumpers for 2 microsteps. A drawback is the low maximum current of 1.2A RMS and 1.7A max.
- I tested the TMC2209 which are soldered into the Farmduino 1.5. The minimum setting are 8 microsteps for them and the Farmduino is not able to send enough steps per time to reach sensible movement speeds. With up to 2.0A RMS they would be a good option to drive the motors mith their maximum torque. The motors should be able to be driven at 1.68A.
- I also Tested the TMC2226 which are very similar to the TMC2209. I hoped that they would run with 2 microsteps but the minimum setting reachable by jumpering is 8 microsteps. Some manucacturers claim that the thermal characteristic of these drivers is better. I think that this is not really relevant as the TMC2209 are basically good enough.
- Because my motors were too weak with the TMC2208 and too slow with the TMC2209 and TMC2226 I switched the driver for the X-axis to a DRV8825. In full step mode they deliver enough torque but they are very loud.
In my eyes the TMC2209 would be the right drivers for a quiet FarmBot. I do not understand why the Farmduino is so slow at sending step impulses to the drivers. Setting high movement speeds in the settings simply has no effect after reaching about 120mm/s with 2 microsteps. The microstep feature seems to be broken anyway because some values in the settings are divided instead of multiplied when activating microsteps.
- One possible fix would be to enable the Farmduino to send step impulses in a faster pace.
- Another would be to configure the TMC2209 via UART. The Farmduino 1.4 is not designed to do that so an external microcontroller would be needed for the configuration. I think it would be possible to use a cheap Arduino for that and just leave the step and dir connection to the Farmduino.
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Pina,
Please note that TMC2208 and TMC2209 and other drivers are “NON-STANDARD HARDWARE” and we can not guarantee that our firmware will be able to support these drivers.
There are just so many different drivers available. With our limited firmware developer time we don’t have the ability to support all different kinds of hardware configurations. In the future, we can not guarantee that these drivers will be supported by the firmware.
The A4988 Stepper Drivers are the ones that we selected and there is a current adjustment on the driver that helps us manage power.
I did not pick the wrong drivers by accident. The A4988 only supports a motor current of 1A (2A max) which is less than the motors can handle. They also have no silent mode and in full step mode the movements of the motors are very loud.
The STEP / DIR interface is standardized so a lot of different drivers support the same interface. Modern drivers like the TMC2209 can be configured and driven via UART but this mode needs support in the firmware. I tested different drivers which do not need firmware modifications. Some of them might seem attractive for FarmBot owners with need for a silent bot but they introduce problems one might not think of initially. That is the reason why I documented the results of my experiments here.
@Marc Talking about firmware support: Why is the Farmduino so very slow at sending STEP pulses to the drivers? 3D printer mainboards can send tens of thousands of pulses per second with the same processor.
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@RickCarlino Does this mean I can install my Farmduino 1.5 and the setting activates StealthChop? It would be very awesome if the feature is already working!
@pinae Not yet, unfortunately. There were some last-minute issues as @stre1026 mentioned. All the wiring is there though. We’re getting closer but not ready yet. PS: I saw your recent activity for the TOF sensor. Really excited to see your progress. Happy to help however I can, let me know. The UART helpers should be ready on the Lua side.