Using SPI only for stepper control December 11, 2017 12:21PM |
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Re: Using SPI only for stepper control December 11, 2017 12:50PM |
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Re: Using SPI only for stepper control December 11, 2017 06:11PM |
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Re: Using SPI only for stepper control January 10, 2020 03:00PM |
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Re: Using SPI only for stepper control January 10, 2020 05:16PM |
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Re: Using SPI only for stepper control January 10, 2020 10:11PM |
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Re: Using SPI only for stepper control January 11, 2020 04:03AM |
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Quote
newbob
Trinamic datasheets do not recommend external clock above 16Mhz (and they lowered max clock from 20 to 18MHz with newer ICs). I always assumed this was due to EMI - could you point out the reasons why external clock does not work well with TMC266x?
Re: Using SPI only for stepper control January 11, 2020 01:05PM |
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Re: Using SPI only for stepper control January 12, 2020 10:07AM |
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Quote
newbob
EN LOW will power down driver's MOSFETs, so one could attach clock fail detect circuit to EN pin when clock fails.
EDIT: datasheet says to disable MOSFETs with EN before shutting down the clock. Well, if pulling EN low will not work than shutting off VCC_IO will, for sure.
Re: Using SPI only for stepper control January 20, 2020 06:29PM |
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Re: Using SPI only for stepper control January 23, 2020 09:29PM |
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Re: Using SPI only for stepper control January 24, 2020 11:15AM |
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Quote
newbob
SPI overhead is large and I'm not sure how feasible it is to communicate with the drivers quickly and reliably, but there's a big incentive to to it: When controlling coil current directly, MCU has much better understanding how much mechanical force is being generated. STEP pulses mask that as MCU does not know if given STEP is a microstep. Microsteps can be up to 4 times weaker than a full step, plus, force is not linear. 3d printers would benefit from only using, say, quarter step resolution for positioning while 'dithering' microsteps in between for smoother operation.
Re: Using SPI only for stepper control January 24, 2020 02:05PM |
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Re: Using SPI only for stepper control January 28, 2024 04:54AM |
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Re: Using SPI only for stepper control March 07, 2024 06:04AM |
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Re: Using SPI only for stepper control March 09, 2024 06:56AM |
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