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Topic: Adapt A Stepper Driver Board to Step & Direction Inputs (Read 978 times) previous topic - next topic


Hi all,

I am trying to get several driver boards / motor combos I have working. They are all based on same board setup and can drive 2 phase (8 lead) and 5 phase motors. The boards control either 4 or 5 phases/windings but I believe that the '4 phase' driver boards pair the appropriate windings and that treatment was done by/on the core processor board  (the 5 phase version has an additional driver module populated and uses 5 inputs not 4).  I have traced out and id'd all chips on board and made a schematic.

I am looking for some guidance.  I need to translate step/direction signals to phase driver chip A & Anot and B & Bnot signals at ttl levels. Put simply, using 4 or 5 'phase wires', a strobe line sets the states for each of the driver chips on the Anot side of the driver chip and then uses the same 4 or 5 'phase wires' and the next strobe to set the state for the A side of the bridge chips.

I would like opinions on how fast would the Arduinos be able to step through a 4 or 5 bit wide table containing a bit pattern that reflects the proper states, incrementing a pointer based on reading a step pulse input bit and using direction input pin to determine which way to increment the pointer, read the table and apply the value to output pins, then set strobe output pin hi and back low,  increment the pointer and read the next table value and output that value, set strobe high and then low. and wait for the next step pulse.   If I have it correct, this table will be twice as long as one complete ?commutation? cycle (not revolution). I have trouble (ADD) following the sequence through so forgive me if this isn't quite correct. Trying to keep the states for a 5 phase motor driver bridge correct is a nightmare - especially with this method!

  • I don't want to spend a lot (anything really) on software to program the microcontroller (I use both windows and Ubuntu).

  • I also dont want to get tied up with programmers etc. both for cost and simplicity reasons.

  • I would like to use USB to program.

  • I would like the device to be less than $35.00 all in.

  • I would also like this chip to be as fast as possible. I want the limiting factor to be the motor and drivers, not the chip.

  • I want to to fully test the motors to get a better idea whether or not to keep the drivers or replace them with newer types. I will have current and power data after testing with this solution I am seeking which will aid in driver selection.

  • For the 5 phase combos, I don't want to spend $$ for a 5 phase driver -they are scarce and expensive! So, in that case I will want to dedicate the test chip(s) to those driver interface(s).

  • I want to have the full performance of the motor driver combo available and not be limited by  the microcontroller - especially for the 5 phase units.

  • Ultimately, I might want  tackle removing the latch chips, make a daughterboard, and use the microcontroller's unused I/O to control the driver chips directly. This might also open option to use PWM capabilities of controller to microstep (maybe).

Thakns to all who struggled through my post. I tried to make be clear without getting bogged down in details...



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