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BigTreeTech TMC5160 and other questions


andrea tasselli
 

Hi everyone,

I'm building my 2nd BluePill and this goes with the BTT TMC5160 v1.2. If I understand correctly from the Wiki I only have to cut out the CLK pin while all the voltage regulation kerfuffle is done via Config.h. The motors this one has to drive are considerable bigger than the previous ones, at 1.4A max per phase. I normally use a running current in my FS-2 setup of 800 mA. Would that be all right for the TMCs as well as per standard operation of OnStep? Mind you, I can live with lower slewing speeds (I slew the mount currently at 300x sidereal).

I plan to use the BME280 on top of the focuser motor. Also, I'd like to have the full NGC/IC catalog on board. What is the best choice in terms of performance vis-a-vis OnStep version?

Finally, I'm also planning and working for replacing the current motor set-up on the CI-700 mount. Any word of wisdom on this one?

Cheers

Andrea
 


Khalid Baheyeldin
 

On Fri, Nov 20, 2020 at 10:30 AM, andrea tasselli wrote:
I'm building my 2nd BluePill and this goes with the BTT TMC5160 v1.2. If I understand correctly from the Wiki I only have to cut out the CLK pin while all the voltage regulation kerfuffle is done via Config.h. The motors this one has to drive are considerable bigger than the previous ones, at 1.4A max per phase. I normally use a running current in my FS-2 setup of 800 mA. Would that be all right for the TMCs as well as per standard operation of OnStep? Mind you, I can live with lower slewing speeds (I slew the mount currently at 300x sidereal).
I am using the BigTree Tech V1.2 TMC5160 with the FYSETC S6, and it works well.
I did not need to cut or solder any CLK wires or pins, and are no ill effects.

The motors I are tiny NEMA11 geared steppers. They ran well at 0.67A with the LV8729.
However, they would stall with the TMC5160, until I changed the IGOTO to the following:

    #define AXIS1_DRIVER_MODEL     TMC5160
    #define AXIS1_DRIVER_IRUN     675
    #define AXIS1_DRIVER_IGOTO    850

    #define AXIS2_DRIVER_MODEL     TMC5160
    #define AXIS2_DRIVER_IRUN     675
    #define AXIS2_DRIVER_IGOTO    850

I keep the slewing speed to 3.5 deg/sec, which is fast enough but still safe.

I did not try the TMC5160 with the Blue Pill PCB, though ...

Also, I'd like to have the full NGC/IC catalog on board.
This is not possible. None of the OnStep boards would have enough storage for the entire NGC catalog.
However, the Android App has that catalog, and so does the ESP32 SHC.

Finally, I'm also planning and working for replacing the current motor set-up on the CI-700 mount. Any word of wisdom on this one?
Check the Showcase page on the Wiki. There are a few of these and similar mounts (G11).