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Other micros that have PIC-like "Quadrature Encoder" on-chip?

Discussion in 'Embedded' started by valemike, Jun 20, 2005.

  1. valemike

    valemike Guest

    I have an application where i'd want to use the 'quadrature encoder' on
    the PIC, especially since it has programmable filtering capabilities.

    However, there are so many erratas with using the deadtime feature in
    their PWM modules that i'm sure to get some shoot-through.

    Does anyone know if there are any Freescale (preferably M68HC09) parts
    that would be functionally equivalent to the PIC18F4431, i.e. have
    quadrature encoder pins, and enhanced PWM capabilities for motors?

    Thanks,
    Mike
     
    valemike, Jun 20, 2005
    #1
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  2. valemike

    Jack Klein Guest

    Can't speak about Freescale directly, but I imaging they have some
    parts that will do this in the 56K DSP series. There are also some
    HS12 parts with PWM, don't know about dead-band capacities.

    TI has a whole series of 32-bit fixed point DSPs in the TMS320F28xx
    family that have timers that do quadrature decoding, including zeroing
    the count on an index pulse if you want. And they have very flexible
    PWMs with simple dead-band control.

    Some of the newer parts are quite reasonably priced.

    --
    Jack Klein
    Home: http://JK-Technology.Com
    FAQs for
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    Jack Klein, Jun 21, 2005
    #2
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  3. valemike

    David Brown Guest

    There are some 8-bit Freescale parts with very flexible PWM units for
    motor control. I think you'd have to use ordinary timer inputs for
    encoder inputs, however. But since the PWM unit does a lot of the work
    already, that should not be too much of a hardship unless you are
    running at very high speeds. Stepping up, there are 56k "hybrid" DSPs
    with everything you need for motor control. I haven't used them myself,
    but I've seen them demonstrated, and was impressed.
     
    David Brown, Jun 21, 2005
    #3
  4. valemike

    valemike Guest

    Thanks Jack and David!

    yup, looks like the MC56XXX are what I should look into. There are a
    few specialized 18F pics to do some specialized motor functions as well
    as quad decoder interfaces as well, but like i said, i'd have to
    investigate if their latest erratas fix the deadtime injection
    problems. There's also the dSPIC, which seems to be equivalent to
    Freescale's 56K. Can't get into TI's parts, or else it would be a whole
    new learning curve!

    Oh well, now i need to get either the Code Warrior compiler (56K),
    Hi-Tech compiler or free 60-day dSPIC compiler (dSPIC).

    -Mike
     
    valemike, Jun 21, 2005
    #4
  5. valemike

    Alex Gibson Guest

    www.newmicros.com look at their pod products (56f805 and 56f807)
    they also have a new one on the way using the 56f8355


    Alex
     
    Alex Gibson, Jun 22, 2005
    #5
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